codeforces-1023 C Bracket Subsequence

#include <iostream>
#include <unordered_map>
#include <algorithm>
#include <vector>
#include <queue>

using namespace std;

int main()
{
    int n,k;
    while(cin >> n >> k)
    {
        string input;
        cin >> input;
        string result;
        int right_existed = 0;
        int left = 0;
        int right = 0;
        for(int i = 0; i < n; i ++)
        {
            if(right_existed!=k/2)
            {
                result += input[i];
                if(input[i]=='(')
                {
                    right_existed ++;
                    left ++;
                }
                else
                    right ++;
            }
        }
        int tmp = left - right;
        while(tmp--)
            result += ')';
        cout << result << endl;
    }
    return 0;
}