func_code_string: #include <bits/stdc++.h>   int main() {     std::ios_base::sync_with_stdio(false);     int n;     std::cin >> n;     std::vector<std::vector<bool> > g(n, std::vector<bool>(n, 0));     for (int row = 0; row < n; row++) {       std::string s;       std::cin >> s;       for (int col = 0; col < s.size(); col++) {         g[row][col] = s[col] -  0 ;       }     }     std::vector<int> a(n);     for (int p = 0; p < n; p++) {       std::cin >> a[p];     }     bool done(false);     std::vector<int> guests;     while (!done) {       done = true;       for (int p = 0; p < n; p++) {         if (a[p] != 0) {           continue;         }         done = false;         guests.push_back(p);         for (int q = 0; q < n; q++) {           a[q] -= g[p][q];         }         break;       }     }     std::cout << guests.size() << std::endl;     for (int p = 0; p < guests.size(); p++) {       std::cout << (1 + guests[p]) << std::endl;     }     return 0;   }   