LeetCode in TypeScript
67. Add Binary
Easy
Given two binary strings a and b, return their sum as a binary string.
Example 1:
Input: a = “11”, b = “1”
Output: “100”
Example 2:
Input: a = “1010”, b = “1011”
Output: “10101”
Constraints:
1 <= a.length, b.length <= 104aandbconsist only of'0'or'1'characters.- Each string does not contain leading zeros except for the zero itself.
Solution
function addBinary(a: string, b: string): string {
const aArray = a.split('')
const bArray = b.split('')
let sb: string[] = []
let i = aArray.length - 1
let j = bArray.length - 1
let carry = 0
while (i >= 0 || j >= 0) {
const digitA = i >= 0 ? parseInt(aArray[i]) : 0
const digitB = j >= 0 ? parseInt(bArray[j]) : 0
const sum = digitA + digitB + carry
sb.push((sum % 2).toString())
carry = Math.floor(sum / 2)
i--
j--
}
if (carry !== 0) {
sb.push(carry.toString())
}
return sb.reverse().join('')
}
export { addBinary }