func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1e5 + 5;   int prefix[N];   int main() {     string s;     int n, k;     cin >> n >> k >> s;     for (int i = int(1); i <= int(n); i++)       prefix[i] = prefix[i - 1] +  1  - s[i - 1];     int ans = n + 1;     for (int i = int(1); i <= int(n); i++) {       if (s[i - 1] ==  0 ) {         int l = 0, r = n - 1;         while (l + 1 < r) {           int mid = (l + r) >> 1;           int L = i - mid, R = i + mid;           L = max(1, L), R = min(n, R);           if (prefix[R] - prefix[L - 1] > k)             r = mid;           else             l = mid;         }         ans = min(ans, r);       }     }     cout << ans << endl;     return 0;   }   