func_code_string: #include <bits/stdc++.h>   using namespace std;   string s;   vector<int> v;   set<double> S;   set<double>::iterator it, it2;   int main() {     int n, k;     cin >> n >> k;     cin >> s;     for (int i = 0; i < s.size(); i++)       if (s[i] ==  0 ) v.push_back(i + 1);     int i = 0, j = 0;     for (i = 0; i <= k; i++) S.insert(v[i]);     j = i - 1;     i = 0;     int mn = INT_MAX;     n = v.size();     while (j < n) {       double x = (v[i] + v[j]) / 2.0;       it = S.lower_bound(x);       it2 = it;       it2--;       int a = max(v[j] - *it, *it - v[i]);       int b = max(*it2 - v[i], v[j] - *it2);       mn = min(mn, min(a, b));       j++;       if (j < n) {         S.erase(v[i]);         S.insert(v[j]);         i++;       }     }     cout << mn;     return 0;   }   