Binary Tree K level sum (samsung)

Given a binary tree and a number K, the task is to find sum of tree nodes at level k. The Binary Tree s given in string form: (node-value(left-subtree)(right-subtree)).

Input:
The first line of input contains an integer T denoting the no of test cases. Then T test cases follow. Each test case contains an integer K denoting level of Binary Tree for which we need sum. Next line is string which represents Binary Tree.

Output:
Print the Sum of all the elements at k level in each line.

Constraints:
1<=T<=100
1<=K<=20

Example:
Input:
1
2 
(0(5(6()())(4()(9()())))(7(1()())(3()())))
Output: 
14
Explaination:
The Tree from the above String will formed as:
                             0
                          /     \
                       5         7
                    /      \     /    \
                   6       4    1     3
                             \

                             9 

最开始被输入方式迷了，其实括号就可以帮我们判断处于第几层！！！

#include <bits/stdc++.h>using namespace std;int main() {int T;cin >> T;while(T--) {    int k;    cin >> k;    string str;    cin >> str;    int ans = 0;    int lev = 0;    for(int i = 0; str[i]; ++i) {        if(str[i] == '(') {            lev++;        } else if(str[i] == ')') {            lev--;        } else if(lev == k+1) {            int j = i+1;            while(str[j] != '(' && str[j] != ')') j++;            int tmp = 0, p = 1;            for(int k = j-1; k >= i; --k) {                tmp += (str[k] - '0') * p;                p *= 10;            }            ans += tmp;            i = j-1;        }    }    cout << ans << endl;}return 0;}