func_code_string: #include <bits/stdc++.h>   using namespace std;   int N, uz[1005], kay;   char ar[1005][1005], k[1005];   int kontrol(int a, int say) {     for (int i = 1; i <= uz[a] - say + 1; i++) {       if (ar[a][i] == k[1]) {         int m = 1, j, k1;         for (j = i + 1, k1 = 2; j <= uz[a] && k1 <= say && m; j++, k1++)           if (ar[a][j] != k[k1]) m = 0;         if (m) {           return 0;         }       }     }     return 1;   }   int maxs = 0;   void oku() {     cin >> N;     for (int i = 1; i <= N; i++) {       scanf(  %s , ar[i] + 1);       uz[i] = strlen(ar[i] + 1);       maxs = max(maxs, uz[i]);     }     int o = 1, l;     k[o] =  a ;     k[o]--;     while (o <= maxs) {       l = 1;       if (k[o] !=  z )         k[o]++;       else {         int p1 = o;         while (p1) {           if (k[p1] !=  z ) {             k[p1]++;             break;           } else             p1--;         }         if (!p1) {           memset(k, 0, sizeof(k));           o++;           for (int i = 1; i <= o; i++) k[i] =  a ;         } else {           p1++;           while (p1 <= o) {             k[p1] =  a ;             p1++;           }         }       }       l = 1;       for (int i = 1; i <= N && l; i++) l = kontrol(i, o);       if (l) {         printf( %s n , k + 1);         return;       }     }   }   int main() {     oku();     return 0;   }   