Bracket Problem (Asked in Toptal Interview )

bracket-problem.js

'use strict';

function solution(S) {
    var arr = [];
    var K = 0;
    for (var i=0; i<S.length; i++) {
        if (S[i]=='(') {
            arr.push(S[i]);
        } else {
            if(arr.length){
                arr.pop();
            }
            K++;
        }
    }
    return K;
}

You are given a string S containing of N brackets, opening"(" and/or closing ")". The goal is to split S into two parts (left and right), such that the number of opening brackets in the left part is eaual to the number of closing brackets in the right part. More formally we lookingfor an integer K such that:

0<=K<=N, and
the numbers of opening brackets in the K leading characters of S is the same as the number of closing brackets in the N-K training characters of S.
Write a function:
function solution(S);

that, given string S, returns a value for K that satisfies the above conditions. It can be shown that such a number K always exists and is unique.

Hi abhinav,
Thanks for sharing. what were the other two problems? I am preparing for Toptal. I would like to know the difficulty level of problems asked