func_code_string: #include <bits/stdc++.h>   using namespace std;   int x;   char s[100005];   bool flag[500];   int cnt[500];   vector<char> f;   int main() {     scanf( %d , &x);     scanf( %s , s);     int len = strlen(s);     for (int i = 0; i < len; i++) cnt[s[i]]++;     for (int i =  a ; i <=  z ; i++) {       if (cnt[i] == 0) continue;       flag[i] = 1;       int pre = -1;       bool tag = 0;       f.push_back(char(i));       for (int j = 0; j < len; j++) {         if (flag[s[j]]) {           pre = j;           continue;         }         int y = j - pre;         if (y >= x) {           tag = 1;           break;         }       }       if (tag)         continue;       else {         cnt[i] = 0;         flag[i] = 0;         int pos = -1;         int pre = -1;         for (int j = 0; j < len; j++) {           if (s[j] == i) {             pos = max(pos, j);           }           if (flag[s[j]]) {             pre = j;             continue;           }           int y = j - pre;           if (y >= x) {             pre = pos;             cnt[i]++;           }         }         break;       }     }     string ans =   ;     int p = f.size();     for (int i = 0; i < p; i++) {       for (int j = 1; j <= cnt[f[i]]; j++) ans += f[i];     }     cout << ans << endl;     return 0;   }   