func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, m, a, b;     cin >> n >> m;     if (m == n) {       vector<bool> rev(n, false);       vector<vector<int> > mat(n + 1);       for (int i = 0; i < m; i++) {         cin >> a >> b;         mat[a].push_back(b);         mat[b].push_back(a);       }       int cont = 0;       for (int i = 1; i <= m; i++) {         if (!rev[i]) {           cont++;           queue<int> COLA;           COLA.push(i);           rev[i] = true;           while (!COLA.empty()) {             int j = COLA.front();             COLA.pop();             for (int k = 0; k < mat[j].size(); k++) {               if (!rev[mat[j][k]]) {                 rev[mat[j][k]] = 1;                 COLA.push(mat[j][k]);               }             }           }         }       }       if (cont == 1)         cout <<  FHTAGN! n ;       else         cout <<  NO n ;     } else       cout <<  NO n ;     return 0;   }   