LeetCode in TypeScript

“For coding interview preparation, LeetCode is one of the best online resource providing a rich library of more than 300 real coding interview questions for you to practice from using one of the 7 supported languages - C, C++, Java, Python, C#, JavaScript, Ruby.”

Data Structure I

Day 1 Array

0053 Maximum Subarray Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 66 90.36

Day 2 Array

0001 Two Sum Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) 54 91.72

Day 3 Array

0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 56 99.56

Day 4 Array

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Day 5 Array

0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 45 96.82

Day 6 String

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Day 7 Linked List

0141 Linked List Cycle Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 59 93.37
0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) 59 86.77

Day 8 Linked List

0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) 51 92.87

Day 9 Stack Queue

0020 Valid Parentheses Easy Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Big_O_Time_O(n)_Space_O(n) 50 95.90

Day 10 Tree

0094 Binary Tree Inorder Traversal Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Big_O_Time_O(n)_Space_O(n) 45 97.30

Day 11 Tree

0102 Binary Tree Level Order Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) 60 97.47
0104 Maximum Depth of Binary Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H) 51 97.14
0101 Symmetric Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(log(N)) 49 98.54

Day 12 Tree

0226 Invert Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 52 81.65

Day 13 Tree

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Day 14 Tree

0098 Validate Binary Search Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N)) 51 98.35

Data Structure II

Day 1 Array

0136 Single Number Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) 56 85.48
0169 Majority Element Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 50 96.16
0015 3Sum Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2) 148 92.62

Day 2 Array

0075 Sort Colors Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 43 97.41
0056 Merge Intervals Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n) 84 92.06

Day 3 Array

0048 Rotate Image Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Big_O_Time_O(n^2)_Space_O(1) 45 95.31

Day 4 Array

0240 Search a 2D Matrix II Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer, Big_O_Time_O(n+m)_Space_O(1) 58 64.44

Day 5 Array

0238 Product of Array Except Self Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Prefix_Sum, Big_O_Time_O(n^2)_Space_O(n) 89 64.48
0560 Subarray Sum Equals K Medium Top_100_Liked_Questions, Array, Hash_Table, Prefix_Sum, Big_O_Time_O(n)_Space_O(n) 70 92.45

Day 6 String

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Day 7 String

0763 Partition Labels Medium Top_100_Liked_Questions, String, Hash_Table, Greedy, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 54 94.74

Day 8 String

0049 Group Anagrams Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n) 93 97.29

Day 9 String

0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 68 95.34

Day 10 Linked List

0002 Add Two Numbers Medium Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Big_O_Time_O(max(N,M))_Space_O(max(N,M)) 92 77.86
0142 Linked List Cycle II Medium Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 59 94.39

Day 11 Linked List

0160 Intersection of Two Linked Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(M+N)_Space_O(1) 67 93.58

Day 12 Linked List

0024 Swap Nodes in Pairs Medium Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) 59 62.67

Day 13 Linked List

0025 Reverse Nodes in k-Group Hard Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(k) 74 66.83

Day 14 Stack Queue

0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N) 84 92.72

Day 15 Tree

0105 Construct Binary Tree from Preorder and Inorder Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Big_O_Time_O(N)_Space_O(N) 65 96.47

Day 16 Tree

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Day 17 Tree

0230 Kth Smallest Element in a BST Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n) 54 97.22

Day 18 Tree

0236 Lowest Common Ancestor of a Binary Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 59 96.11

Day 19 Graph

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Day 20 Heap Priority Queue

0215 Kth Largest Element in an Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Heap_Priority_Queue, Divide_and_Conquer, Quickselect, Big_O_Time_O(n*log(n))_Space_O(log(n)) 148 54.45
0347 Top K Frequent Elements Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Heap_Priority_Queue, Counting, Divide_and_Conquer, Quickselect, Bucket_Sort, Big_O_Time_O(n*log(n))_Space_O(k) 62 87.48

Day 21 Heap Priority Queue

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Algorithm I

0035 Search Insert Position Easy Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 51 80.95

Day 2 Two Pointers

0189 Rotate Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 75 97.25

Day 3 Two Pointers

0283 Move Zeroes Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 71 91.63

Day 4 Two Pointers

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Day 5 Two Pointers

0019 Remove Nth Node From End of List Medium Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Big_O_Time_O(L)_Space_O(L) 54 87.87

Day 6 Sliding Window

0003 Longest Substring Without Repeating Characters Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1) 65 90.77

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Day 10 Recursion Backtracking

0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) 59 86.77
0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) 51 92.87

Day 11 Recursion Backtracking

0046 Permutations Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!) 56 96.26

Day 12 Dynamic Programming

0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) 44 94.58
0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 51 77.29

Day 13 Bit Manipulation

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Day 14 Bit Manipulation

0136 Single Number Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) 56 85.48

Algorithm II

Day 1 Binary Search

0034 Find First and Last Position of Element in Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 45 98.05
0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 43 98.54
0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 45 96.82
0153 Find Minimum in Rotated Sorted Array Medium Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N) 42 98.87

Day 3 Two Pointers

0015 3Sum Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2) 148 92.62

Day 4 Two Pointers

0011 Container With Most Water Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Greedy, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 57 98.23

Day 5 Sliding Window

0438 Find All Anagrams in a String Medium Top_100_Liked_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n+m)_Space_O(1) 69 96.69
0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(M*N)_Space_O(M*N) 61 96.71

Day 7 Breadth First Search Depth First Search

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Day 8 Breadth First Search Depth First Search

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Day 9 Recursion Backtracking

0078 Subsets Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Big_O_Time_O(2^n)_Space_O(n*2^n) 50 94.61

Day 10 Recursion Backtracking

0039 Combination Sum Medium Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n) 65 86.86

Day 11 Recursion Backtracking

0017 Letter Combinations of a Phone Number Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Big_O_Time_O(4^n)_Space_O(n) 52 79.11
0022 Generate Parentheses Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(2^n)_Space_O(n) 60 62.03
0079 Word Search Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Backtracking, Big_O_Time_O(4^(m*n))_Space_O(m*n) 327 95.78

Day 12 Dynamic Programming

0055 Jump Game Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 58 91.95

Day 13 Dynamic Programming

0045 Jump Game II Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 50 95.93
0062 Unique Paths Medium Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(m*n)_Space_O(m*n) 40 98.97

Day 14 Dynamic Programming

0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 68 95.34

Day 15 Dynamic Programming

0139 Word Break Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max) 56 88.44

Day 16 Dynamic Programming

0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n) 57 93.75

Day 17 Dynamic Programming

1143 Longest Common Subsequence Medium Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n*m)_Space_O(n*m) 94 80.56

Day 18 Dynamic Programming

0072 Edit Distance Hard Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) 68 95.20
0322 Coin Change Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount) 85 86.14

Day 19 Bit Manipulation

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Day 20 Others

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Day 21 Others

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Binary Search I

Day 1

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Day 2

0035 Search Insert Position Easy Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 51 80.95

Day 3

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Day 4

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Day 5

0034 Find First and Last Position of Element in Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 45 98.05

Day 6

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Day 7

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Day 8

0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 45 96.82

Day 9

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Day 10

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Day 11

0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 43 98.54

Day 12

0153 Find Minimum in Rotated Sorted Array Medium Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N) 42 98.87

Binary Search II

Day 1

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Day 2

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Day 3

0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n) 57 93.75

Day 4

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Day 5

0287 Find the Duplicate Number Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Two_Pointers, Bit_Manipulation, Big_O_Time_O(n)_Space_O(n) 60 98.11

Day 6

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Day 7

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Day 8

0240 Search a 2D Matrix II Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer, Big_O_Time_O(n+m)_Space_O(1) 58 64.44

Day 9

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Day 10

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Day 11

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Day 12

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Day 13

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Day 14

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Day 15

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Day 16

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Day 17

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Day 18

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Day 19

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Day 20

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Dynamic Programming I

Day 1

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Day 2

0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) 44 94.58

Day 3

0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 51 77.29

Day 4

0055 Jump Game Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 58 91.95
0045 Jump Game II Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 50 95.93

Day 5

0053 Maximum Subarray Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 66 90.36

Day 6

0152 Maximum Product Subarray Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 53 87.50

Day 7

0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 56 99.56

Day 8

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Day 9

0139 Word Break Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max) 56 88.44
0042 Trapping Rain Water Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(1) 46 99.52

Day 10

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Day 11

0096 Unique Binary Search Trees Medium Top_100_Liked_Questions, Dynamic_Programming, Math, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(1) 45 96.00

Day 12

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Day 13

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Day 14

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Day 15

0062 Unique Paths Medium Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(m*n)_Space_O(m*n) 40 98.97

Day 16

0064 Minimum Path Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(m*n)_Space_O(m*n) 48 99.67
0221 Maximal Square Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(m*n)_Space_O(m*n) 83 79.70

Day 17

0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 68 95.34

Day 18

0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n) 57 93.75

Day 19

1143 Longest Common Subsequence Medium Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n*m)_Space_O(n*m) 94 80.56
0072 Edit Distance Hard Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) 68 95.20

Day 20

0322 Coin Change Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount) 85 86.14

Day 21

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Programming Skills I

Day 1 Basic Data Type

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Day 2 Operator

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Day 3 Conditional Statements

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Day 4 Loop

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Day 5 Function

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Day 6 Array

0283 Move Zeroes Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 71 91.63

Day 7 Array

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Day 8 String

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Day 9 String

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Day 10 Linked List and Tree

0104 Maximum Depth of Binary Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H) 51 97.14

Day 11 Containers and Libraries

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Day 12 Class and Object

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Programming Skills II

Day 1

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Day 2

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Day 3

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Day 4

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Day 5

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Day 6

0739 Daily Temperatures Medium Top_100_Liked_Questions, Array, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(n) 194 97.36

Day 7

0048 Rotate Image Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Big_O_Time_O(n^2)_Space_O(1) 45 95.31

Day 8

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Day 9

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Day 10

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Day 11

0049 Group Anagrams Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n) 93 97.29

Day 12

0438 Find All Anagrams in a String Medium Top_100_Liked_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n+m)_Space_O(1) 69 96.69

Day 13

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Day 14

0138 Copy List with Random Pointer Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Big_O_Time_O(N)_Space_O(N) 52 88.27

Day 15

0002 Add Two Numbers Medium Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Big_O_Time_O(max(N,M))_Space_O(max(N,M)) 92 77.86

Day 16

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Day 17

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Day 18

0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N) 84 92.72

Day 19

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Day 20

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Graph Theory I

0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(M*N)_Space_O(M*N) 61 96.71

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Day 7 Standard Traversal

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Day 8 Standard Traversal

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Day 9 Standard Traversal

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Day 10 Standard Traversal

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Day 13 Graph Theory

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Day 14 Graph Theory

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SQL I

Day 1 Select

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Day 2 Select and Order

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Day 3 String Processing Functions

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Day 4 Union and Select

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Day 5 Union

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Day 6 Union

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Day 7 Function

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Day 8 Function

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Day 9 Control of Flow

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Day 10 Where

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Level 1

Day 1 Prefix Sum

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Day 2 String

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Day 3 Linked List

0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) 59 86.77
0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) 51 92.87

Day 4 Linked List

0142 Linked List Cycle II Medium Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 59 94.39

Day 5 Greedy

0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 56 99.56

Day 6 Tree

0102 Binary Tree Level Order Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) 60 97.47

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Day 8 Binary Search Tree

0098 Validate Binary Search Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N)) 51 98.35

Day 9 Graph/BFS/DFS

0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(M*N)_Space_O(M*N) 61 96.71

Day 10 Dynamic Programming

0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) 44 94.58

Day 11 Dynamic Programming

0062 Unique Paths Medium Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Big_O_Time_O(m*n)_Space_O(m*n) 40 98.97

Day 12 Sliding Window/Two Pointer

0438 Find All Anagrams in a String Medium Top_100_Liked_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n+m)_Space_O(1) 69 96.69

Day 13 Hashmap

0001 Two Sum Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) 54 91.72

Day 14 Stack

0394 Decode String Medium Top_100_Liked_Questions, String, Stack, Recursion, Big_O_Time_O(n)_Space_O(n) 51 81.02

Day 15 Heap

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Level 2

Day 1 Implementation/Simulation

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Day 2 String

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Day 3 Linked List

0019 Remove Nth Node From End of List Medium Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Big_O_Time_O(L)_Space_O(L) 54 87.87
0234 Palindrome Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Stack, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) 96 95.67

Day 4 Linked List

0148 Sort List Medium Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Big_O_Time_O(log(N))_Space_O(log(N)) 141 97.14

Day 5 Greedy

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Day 6 Tree

0226 Invert Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 52 81.65

Day 7 Tree

0543 Diameter of Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 61 80.89
0437 Path Sum III Medium Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 68 86.71
0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 45 96.82
0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 43 98.54

Day 9 Binary Search Tree

0230 Kth Smallest Element in a BST Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n) 54 97.22

Day 10 Graph/BFS/DFS

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Day 11 Graph/BFS/DFS

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Day 12 Dynamic Programming

0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 51 77.29
0322 Coin Change Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Big_O_Time_O(m*n)_Space_O(amount) 85 86.14

Day 13 Dynamic Programming

0416 Partition Equal Subset Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Big_O_Time_O(n*sums)_Space_O(n*sums) 91 74.38
0152 Maximum Product Subarray Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 53 87.50

Day 14 Sliding Window/Two Pointer

0003 Longest Substring Without Repeating Characters Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1) 65 90.77
0076 Minimum Window Substring Hard Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(s.length())_Space_O(1) 82 82.17

Day 15 Tree

0101 Symmetric Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(log(N)) 49 98.54

Day 16 Design

0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N) 84 92.72
0208 Implement Trie (Prefix Tree) Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N) 168 80.99

Day 17 Interval

0056 Merge Intervals Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n) 84 92.06

Day 18 Stack

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Day 19 Union Find

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Day 20 Brute Force/Backtracking

0039 Combination Sum Medium Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n) 65 86.86
0046 Permutations Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!) 56 96.26

Udemy

Udemy Integers

0136 Single Number Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Big_O_Time_O(N)_Space_O(1) 56 85.48
0007 Reverse Integer Medium Top_Interview_Questions, Math 56 95.68
0009 Palindrome Number Easy Math 137 88.64

Udemy Strings

0003 Longest Substring Without Repeating Characters Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1) 65 90.77
0020 Valid Parentheses Easy Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Big_O_Time_O(n)_Space_O(n) 50 95.90
0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 68 95.34
0394 Decode String Medium Top_100_Liked_Questions, String, Stack, Recursion, Big_O_Time_O(n)_Space_O(n) 51 81.02
0049 Group Anagrams Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n*k_log_k)_Space_O(n) 93 97.29
0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 43 98.54
0153 Find Minimum in Rotated Sorted Array Medium Top_100_Liked_Questions, Array, Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N) 42 98.87

Udemy Arrays

0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 56 99.56
0283 Move Zeroes Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 71 91.63
0001 Two Sum Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) 54 91.72
0189 Rotate Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 75 97.25
0055 Jump Game Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) 58 91.95
0075 Sort Colors Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 43 97.41
0238 Product of Array Except Self Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Prefix_Sum, Big_O_Time_O(n^2)_Space_O(n) 89 64.48
0041 First Missing Positive Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) 55 98.51
0239 Sliding Window Maximum Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Heap_Priority_Queue, Sliding_Window, Queue, Monotonic_Queue, Big_O_Time_O(n*k)_Space_O(n+k) 216 99.50

Udemy Two Pointers

0042 Trapping Rain Water Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Big_O_Time_O(n)_Space_O(1) 46 99.52
0015 3Sum Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2) 148 92.62

Udemy Famous Algorithm

0053 Maximum Subarray Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 66 90.36
0169 Majority Element Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Big_O_Time_O(n)_Space_O(1) 50 96.16

Udemy Sorting Algorithms

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Udemy 2D Arrays/Matrix

0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 45 96.82
0048 Rotate Image Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Big_O_Time_O(n^2)_Space_O(1) 45 95.31
0073 Set Matrix Zeroes Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Matrix, Big_O_Time_O(m*n)_Space_O(1) 61 97.66
0056 Merge Intervals Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n) 84 92.06

Udemy Linked List

0114 Flatten Binary Tree to Linked List Medium Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Big_O_Time_O(N)_Space_O(N) 55 90.66
0024 Swap Nodes in Pairs Medium Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) 59 62.67
0142 Linked List Cycle II Medium Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 59 94.39
0141 Linked List Cycle Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(N)_Space_O(1) 59 93.37
0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) 51 92.87
0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) 59 86.77
0160 Intersection of Two Linked Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Big_O_Time_O(M+N)_Space_O(1) 67 93.58
0234 Palindrome Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Stack, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) 96 95.67
0138 Copy List with Random Pointer Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Big_O_Time_O(N)_Space_O(N) 52 88.27
0025 Reverse Nodes in k-Group Hard Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(k) 74 66.83
0146 LRU Cache Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Design, Linked_List, Doubly_Linked_List, Big_O_Time_O(1)_Space_O(capacity) 473 94.72

Udemy Tree Stack Queue

0094 Binary Tree Inorder Traversal Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Big_O_Time_O(n)_Space_O(n) 45 97.30
0102 Binary Tree Level Order Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) 60 97.47
0543 Diameter of Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 61 80.89
0226 Invert Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 52 81.65
0104 Maximum Depth of Binary Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(H) 51 97.14
0124 Binary Tree Maximum Path Sum Hard Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) 61 96.73
0098 Validate Binary Search Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N)) 51 98.35
0236 Lowest Common Ancestor of a Binary Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) 59 96.11

Udemy Trie and Heap

0208 Implement Trie (Prefix Tree) Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N) 168 80.99

Udemy Graph

0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Big_O_Time_O(M*N)_Space_O(M*N) 61 96.71

Udemy Dynamic Programming

0139 Word Break Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Big_O_Time_O(M+max*N)_Space_O(M+N+max) 56 88.44
0152 Maximum Product Subarray Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 53 87.50
0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 51 77.29
0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Big_O_Time_O(n)_Space_O(n) 44 94.58
0064 Minimum Path Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Big_O_Time_O(m*n)_Space_O(m*n) 48 99.67
0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Big_O_Time_O(n*log_n)_Space_O(n) 57 93.75
1143 Longest Common Subsequence Medium Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n*m)_Space_O(n*m) 94 80.56
0072 Edit Distance Hard Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) 68 95.20
0010 Regular Expression Matching Hard Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Recursion, Big_O_Time_O(m*n)_Space_O(m*n) 69 92.65

Udemy Backtracking/Recursion

0022 Generate Parentheses Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(2^n)_Space_O(n) 60 62.03
0039 Combination Sum Medium Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n) 65 86.86
0078 Subsets Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Big_O_Time_O(2^n)_Space_O(n*2^n) 50 94.61
0017 Letter Combinations of a Phone Number Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Big_O_Time_O(4^n)_Space_O(n) 52 79.11
0046 Permutations Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Big_O_Time_O(n*n!)_Space_O(n+n!) 56 96.26

Udemy Bit Manipulation

0338 Counting Bits Easy Top_100_Liked_Questions, Dynamic_Programming, Bit_Manipulation, Big_O_Time_O(num)_Space_O(num) 69 86.81

Udemy Design

0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Big_O_Time_O(1)_Space_O(N) 84 92.72

Algorithms

# Title Difficulty Tag Time, ms Time, %
1143 Longest Common Subsequence Medium Top_100_Liked_Questions, String, Dynamic_Programming, Algorithm_II_Day_17_Dynamic_Programming, Dynamic_Programming_I_Day_19, Udemy_Dynamic_Programming, Big_O_Time_O(n*m)_Space_O(n*m) 94 80.56
0763 Partition Labels Medium Top_100_Liked_Questions, String, Hash_Table, Greedy, Two_Pointers, Data_Structure_II_Day_7_String, Big_O_Time_O(n)_Space_O(1) 54 94.74
0739 Daily Temperatures Medium Top_100_Liked_Questions, Array, Stack, Monotonic_Stack, Programming_Skills_II_Day_6, Big_O_Time_O(n)_Space_O(n) 194 97.36
0647 Palindromic Substrings Medium Top_100_Liked_Questions, String, Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n) 60 89.76
0560 Subarray Sum Equals K Medium Top_100_Liked_Questions, Array, Hash_Table, Prefix_Sum, Data_Structure_II_Day_5_Array, Big_O_Time_O(n)_Space_O(n) 70 92.45
0543 Diameter of Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Level_2_Day_7_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) 61 80.89
0494 Target Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Backtracking, Big_O_Time_O(n*(sum+s))_Space_O(n*(sum+s)) 77 81.99
0438 Find All Anagrams in a String Medium Top_100_Liked_Questions, String, Hash_Table, Sliding_Window, Algorithm_II_Day_5_Sliding_Window, Programming_Skills_II_Day_12, Level_1_Day_12_Sliding_Window/Two_Pointer, Big_O_Time_O(n+m)_Space_O(1) 69 96.69
0437 Path Sum III Medium Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Level_2_Day_7_Tree, Big_O_Time_O(n)_Space_O(n) 68 86.71
0416 Partition Equal Subset Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Level_2_Day_13_Dynamic_Programming, Big_O_Time_O(n*sums)_Space_O(n*sums) 91 74.38
0394 Decode String Medium Top_100_Liked_Questions, String, Stack, Recursion, Level_1_Day_14_Stack, Udemy_Strings, Big_O_Time_O(n)_Space_O(n) 51 81.02
0347 Top K Frequent Elements Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Heap_Priority_Queue, Counting, Divide_and_Conquer, Quickselect, Bucket_Sort, Data_Structure_II_Day_20_Heap_Priority_Queue, Big_O_Time_O(n*log(n))_Space_O(k) 62 87.48
0338 Counting Bits Easy Top_100_Liked_Questions, Dynamic_Programming, Bit_Manipulation, Udemy_Bit_Manipulation, Big_O_Time_O(num)_Space_O(num) 69 86.81
0322 Coin Change Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Breadth_First_Search, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_20, Level_2_Day_12_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(amount) 85 86.14
0300 Longest Increasing Subsequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Binary_Search, Algorithm_II_Day_16_Dynamic_Programming, Binary_Search_II_Day_3, Dynamic_Programming_I_Day_18, Udemy_Dynamic_Programming, Big_O_Time_O(n*log_n)_Space_O(n) 57 93.75
0295 Find Median from Data Stream Hard Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Design, Heap_Priority_Queue, Data_Stream, Big_O_Time_O(n*log_n)_Space_O(n) 335 99.44
0287 Find the Duplicate Number Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Two_Pointers, Bit_Manipulation, Binary_Search_II_Day_5, Big_O_Time_O(n)_Space_O(n) 60 98.11
0283 Move Zeroes Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Two_Pointers, Algorithm_I_Day_3_Two_Pointers, Programming_Skills_I_Day_6_Array, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) 71 91.63
0240 Search a 2D Matrix II Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer, Data_Structure_II_Day_4_Array, Binary_Search_II_Day_8, Big_O_Time_O(n+m)_Space_O(1) 58 64.44
0239 Sliding Window Maximum Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Heap_Priority_Queue, Sliding_Window, Queue, Monotonic_Queue, Udemy_Arrays, Big_O_Time_O(n*k)_Space_O(n+k) 216 99.50
0238 Product of Array Except Self Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Prefix_Sum, Data_Structure_II_Day_5_Array, Udemy_Arrays, Big_O_Time_O(n^2)_Space_O(n) 89 64.48
0236 Lowest Common Ancestor of a Binary Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Data_Structure_II_Day_18_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) 59 96.11
0234 Palindrome Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Stack, Linked_List, Recursion, Level_2_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(1) 96 95.67
0230 Kth Smallest Element in a BST Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Data_Structure_II_Day_17_Tree, Level_2_Day_9_Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n) 54 97.22
0226 Invert Binary Tree Easy Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_12_Tree, Level_2_Day_6_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) 52 81.65
0221 Maximal Square Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Dynamic_Programming_I_Day_16, Big_O_Time_O(m*n)_Space_O(m*n) 83 79.70
0215 Kth Largest Element in an Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Heap_Priority_Queue, Divide_and_Conquer, Quickselect, Data_Structure_II_Day_20_Heap_Priority_Queue, Big_O_Time_O(n*log(n))_Space_O(log(n)) 148 54.45
0208 Implement Trie (Prefix Tree) Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Level_2_Day_16_Design, Udemy_Trie_and_Heap, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N) 168 80.99
0207 Course Schedule Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Graph, Topological_Sort, Big_O_Time_O(N)_Space_O(N) 68 70.14
0206 Reverse Linked List Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Data_Structure_I_Day_8_Linked_List, Algorithm_I_Day_10_Recursion_Backtracking, Level_1_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) 51 92.87
0200 Number of Islands Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Depth_First_Search, Breadth_First_Search, Matrix, Union_Find, Algorithm_II_Day_6_Breadth_First_Search_Depth_First_Search, Graph_Theory_I_Day_1_Matrix_Related_Problems, Level_1_Day_9_Graph/BFS/DFS, Udemy_Graph, Big_O_Time_O(M*N)_Space_O(M*N) 61 96.71
0198 House Robber Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Algorithm_I_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_3, Level_2_Day_12_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 51 77.29
0189 Rotate Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Two_Pointers, Algorithm_I_Day_2_Two_Pointers, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) 75 97.25
0169 Majority Element Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Sorting, Counting, Divide_and_Conquer, Data_Structure_II_Day_1_Array, Udemy_Famous_Algorithm, Big_O_Time_O(n)_Space_O(1) 50 96.16
0160 Intersection of Two Linked Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Data_Structure_II_Day_11_Linked_List, Udemy_Linked_List, Big_O_Time_O(M+N)_Space_O(1) 67 93.58
0155 Min Stack Easy Top_100_Liked_Questions, Top_Interview_Questions, Stack, Design, Data_Structure_II_Day_14_Stack_Queue, Programming_Skills_II_Day_18, Level_2_Day_16_Design, Udemy_Design, Big_O_Time_O(1)_Space_O(N) 84 92.72
0153 Find Minimum in Rotated Sorted Array Medium Top_100_Liked_Questions, Array, Binary_Search, Algorithm_II_Day_2_Binary_Search, Binary_Search_I_Day_12, Udemy_Binary_Search, Big_O_Time_O(log_N)_Space_O(log_N) 42 98.87
0152 Maximum Product Subarray Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Dynamic_Programming_I_Day_6, Level_2_Day_13_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) 53 87.50
0148 Sort List Medium Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Level_2_Day_4_Linked_List, Big_O_Time_O(log(N))_Space_O(log(N)) 141 97.14
0146 LRU Cache Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Design, Linked_List, Doubly_Linked_List, Udemy_Linked_List, Big_O_Time_O(1)_Space_O(capacity) 473 94.72
0142 Linked List Cycle II Medium Top_100_Liked_Questions, Hash_Table, Two_Pointers, Linked_List, Data_Structure_II_Day_10_Linked_List, Level_1_Day_4_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) 59 94.39
0141 Linked List Cycle Easy Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Two_Pointers, Linked_List, Data_Structure_I_Day_7_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) 59 93.37
0139 Word Break Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Dynamic_Programming, Trie, Memoization, Algorithm_II_Day_15_Dynamic_Programming, Dynamic_Programming_I_Day_9, Udemy_Dynamic_Programming, Big_O_Time_O(M+max*N)_Space_O(M+N+max) 56 88.44
0138 Copy List with Random Pointer Medium Top_100_Liked_Questions, Top_Interview_Questions, Hash_Table, Linked_List, Programming_Skills_II_Day_14, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(N) 52 88.27
0136 Single Number Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Data_Structure_II_Day_1_Array, Algorithm_I_Day_14_Bit_Manipulation, Udemy_Integers, Big_O_Time_O(N)_Space_O(1) 56 85.48
0131 Palindrome Partitioning Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Big_O_Time_O(N*2^N)_Space_O(2^N*N) 203 99.22
0128 Longest Consecutive Sequence Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Union_Find, Big_O_Time_O(N_log_N)_Space_O(1) 92 93.69
0124 Binary Tree Maximum Path Sum Hard Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(N) 61 96.73
0121 Best Time to Buy and Sell Stock Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Data_Structure_I_Day_3_Array, Dynamic_Programming_I_Day_7, Level_1_Day_5_Greedy, Udemy_Arrays, Big_O_Time_O(N)_Space_O(1) 56 99.56
0114 Flatten Binary Tree to Linked List Medium Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(N) 55 90.66
0105 Construct Binary Tree from Preorder and Inorder Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Data_Structure_II_Day_15_Tree, Big_O_Time_O(N)_Space_O(N) 65 96.47
0104 Maximum Depth of Binary Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Programming_Skills_I_Day_10_Linked_List_and_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(H) 51 97.14
0102 Binary Tree Level Order Traversal Medium Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Level_1_Day_6_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(N) 60 97.47
0101 Symmetric Tree Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Level_2_Day_15_Tree, Big_O_Time_O(N)_Space_O(log(N)) 49 98.54
0098 Validate Binary Search Tree Medium Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Data_Structure_I_Day_14_Tree, Level_1_Day_8_Binary_Search_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(log(N)) 51 98.35
0096 Unique Binary Search Trees Medium Top_100_Liked_Questions, Dynamic_Programming, Math, Tree, Binary_Tree, Binary_Search_Tree, Dynamic_Programming_I_Day_11, Big_O_Time_O(n)_Space_O(1) 45 96.00
0094 Binary Tree Inorder Traversal Easy Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Data_Structure_I_Day_10_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) 45 97.30
0084 Largest Rectangle in Histogram Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Stack, Monotonic_Stack, Big_O_Time_O(n_log_n)_Space_O(log_n) 78 92.44
0079 Word Search Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Big_O_Time_O(4^(m*n))_Space_O(m*n) 327 95.78
0078 Subsets Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Bit_Manipulation, Backtracking, Algorithm_II_Day_9_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n*2^n) 50 94.61
0076 Minimum Window Substring Hard Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Level_2_Day_14_Sliding_Window/Two_Pointer, Big_O_Time_O(s.length())_Space_O(1) 82 82.17
0075 Sort Colors Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Data_Structure_II_Day_2_Array, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) 43 97.41
0074 Search a 2D Matrix Medium Top_100_Liked_Questions, Array, Binary_Search, Matrix, Data_Structure_I_Day_5_Array, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_8, Level_2_Day_8_Binary_Search, Udemy_2D_Arrays/Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) 45 96.82
0073 Set Matrix Zeroes Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Matrix, Udemy_2D_Arrays/Matrix, Big_O_Time_O(m*n)_Space_O(1) 61 97.66
0072 Edit Distance Hard Top_100_Liked_Questions, String, Dynamic_Programming, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_19, Udemy_Dynamic_Programming, Big_O_Time_O(n^2)_Space_O(n2) 68 95.20
0070 Climbing Stairs Easy Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Algorithm_I_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_2, Level_1_Day_10_Dynamic_Programming, Udemy_Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) 44 94.58
0064 Minimum Path Sum Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Dynamic_Programming_I_Day_16, Udemy_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(m*n) 48 99.67
0062 Unique Paths Medium Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, Algorithm_II_Day_13_Dynamic_Programming, Dynamic_Programming_I_Day_15, Level_1_Day_11_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(m*n) 40 98.97
0056 Merge Intervals Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Data_Structure_II_Day_2_Array, Level_2_Day_17_Interval, Udemy_2D_Arrays/Matrix, Big_O_Time_O(n_log_n)_Space_O(n) 84 92.06
0055 Jump Game Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Algorithm_II_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_4, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) 58 91.95
0053 Maximum Subarray Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Data_Structure_I_Day_1_Array, Dynamic_Programming_I_Day_5, Udemy_Famous_Algorithm, Big_O_Time_O(n)_Space_O(1) 66 90.36
0051 N-Queens Hard Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(N!)_Space_O(N) 57 93.84
0049 Group Anagrams Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Data_Structure_II_Day_8_String, Programming_Skills_II_Day_11, Udemy_Strings, Big_O_Time_O(n*k_log_k)_Space_O(n) 93 97.29
0048 Rotate Image Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Data_Structure_II_Day_3_Array, Programming_Skills_II_Day_7, Udemy_2D_Arrays/Matrix, Big_O_Time_O(n^2)_Space_O(1) 45 95.31
0046 Permutations Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Backtracking, Algorithm_I_Day_11_Recursion_Backtracking, Level_2_Day_20_Brute_Force/Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(n*n!)_Space_O(n+n!) 56 96.26
0045 Jump Game II Medium Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Algorithm_II_Day_13_Dynamic_Programming, Dynamic_Programming_I_Day_4, Big_O_Time_O(n)_Space_O(1) 50 95.93
0042 Trapping Rain Water Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Dynamic_Programming_I_Day_9, Udemy_Two_Pointers, Big_O_Time_O(n)_Space_O(1) 46 99.52
0041 First Missing Positive Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Udemy_Arrays, Big_O_Time_O(n)_Space_O(n) 55 98.51
0039 Combination Sum Medium Top_100_Liked_Questions, Array, Backtracking, Algorithm_II_Day_10_Recursion_Backtracking, Level_2_Day_20_Brute_Force/Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n+2^n) 65 86.86
0035 Search Insert Position Easy Top_100_Liked_Questions, Array, Binary_Search, Algorithm_I_Day_1_Binary_Search, Binary_Search_I_Day_2, Big_O_Time_O(log_n)_Space_O(1) 51 80.95
0034 Find First and Last Position of Element in Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_5, Big_O_Time_O(log_n)_Space_O(1) 45 98.05
0033 Search in Rotated Sorted Array Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_11, Level_2_Day_8_Binary_Search, Udemy_Binary_Search, Big_O_Time_O(log_n)_Space_O(1) 43 98.54
0032 Longest Valid Parentheses Hard Top_100_Liked_Questions, String, Dynamic_Programming, Stack, Big_O_Time_O(n)_Space_O(1) 56 89.31
0031 Next Permutation Medium Top_100_Liked_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) 47 99.30
0025 Reverse Nodes in k-Group Hard Top_100_Liked_Questions, Linked_List, Recursion, Data_Structure_II_Day_13_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(k) 74 66.83
0024 Swap Nodes in Pairs Medium Top_100_Liked_Questions, Linked_List, Recursion, Data_Structure_II_Day_12_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(1) 59 62.67
0023 Merge k Sorted Lists Hard Top_100_Liked_Questions, Top_Interview_Questions, Heap_Priority_Queue, Linked_List, Divide_and_Conquer, Merge_Sort, Big_O_Time_O(k*n*log(k))_Space_O(log(k)) 76 94.52
0022 Generate Parentheses Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(2^n)_Space_O(n) 60 62.03
0021 Merge Two Sorted Lists Easy Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Data_Structure_I_Day_7_Linked_List, Algorithm_I_Day_10_Recursion_Backtracking, Level_1_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(m+n)_Space_O(m+n) 59 86.77
0020 Valid Parentheses Easy Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Data_Structure_I_Day_9_Stack_Queue, Udemy_Strings, Big_O_Time_O(n)_Space_O(n) 50 95.90
0019 Remove Nth Node From End of List Medium Top_100_Liked_Questions, Top_Interview_Questions, Two_Pointers, Linked_List, Algorithm_I_Day_5_Two_Pointers, Level_2_Day_3_Linked_List, Big_O_Time_O(L)_Space_O(L) 54 87.87
0017 Letter Combinations of a Phone Number Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Backtracking, Algorithm_II_Day_11_Recursion_Backtracking, Udemy_Backtracking/Recursion, Big_O_Time_O(4^n)_Space_O(n) 52 79.11
0015 3Sum Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Two_Pointers, Data_Structure_II_Day_1_Array, Algorithm_II_Day_3_Two_Pointers, Udemy_Two_Pointers, Big_O_Time_O(n*log(n))_Space_O(n^2) 148 92.62
0011 Container With Most Water Medium Top_100_Liked_Questions, Top_Interview_Questions, Array, Greedy, Two_Pointers, Algorithm_II_Day_4_Two_Pointers, Big_O_Time_O(n)_Space_O(1) 57 98.23
0010 Regular Expression Matching Hard Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Recursion, Udemy_Dynamic_Programming, Big_O_Time_O(m*n)_Space_O(m*n) 69 92.65
0009 Palindrome Number Easy Math, Udemy_Integers 137 88.64
0008 String to Integer (atoi) Medium Top_Interview_Questions, String 56 99.01
0007 Reverse Integer Medium Top_Interview_Questions, Math, Udemy_Integers 56 95.68
0006 Zigzag Conversion Medium String 64 95.38
0005 Longest Palindromic Substring Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Data_Structure_II_Day_9_String, Algorithm_II_Day_14_Dynamic_Programming, Dynamic_Programming_I_Day_17, Udemy_Strings, Big_O_Time_O(n)_Space_O(n) 68 95.34
0004 Median of Two Sorted Arrays Hard Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Divide_and_Conquer, Big_O_Time_O(log(min(N,M)))_Space_O(1) 86 92.15
0003 Longest Substring Without Repeating Characters Medium Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Algorithm_I_Day_6_Sliding_Window, Level_2_Day_14_Sliding_Window/Two_Pointer, Udemy_Strings, Big_O_Time_O(n)_Space_O(1) 65 90.77
0002 Add Two Numbers Medium Top_100_Liked_Questions, Top_Interview_Questions, Math, Linked_List, Recursion, Data_Structure_II_Day_10_Linked_List, Programming_Skills_II_Day_15, Big_O_Time_O(max(N,M))_Space_O(max(N,M)) 92 77.86
0001 Two Sum Easy Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Data_Structure_I_Day_2_Array, Level_1_Day_13_Hashmap, Udemy_Arrays, Big_O_Time_O(n)_Space_O(n) 54 91.72