func_code_string: #include <bits/stdc++.h>   using namespace std;   int N, M;   bool conn[8][8];   int a, b;   int v[8];   int cur;   bool used[8][8];   int best, cur2, cur3, cur4, ans;   int main() {     cin >> N >> M;     for (int i = 0; i < M; i++) {       cin >> a >> b;       conn[a][b] = conn[b][a] = true;     }     for (int i = 0; i < 279936; i++) {       cur = i;       for (int j = 0; j < 6; j++) {         for (int k = 0; k < 6; k++) {           used[j][k] = false;         }       }       for (int j = 0; j < 7; j++) {         v[j] = cur % 6;         cur /= 6;       }       cur2 = 0;       for (int j = 1; j <= N; j++) {         for (int k = j + 1; k <= N; k++) {           if (conn[j][k]) {             cur3 = v[j];             cur4 = v[k];             if (cur3 > cur4) {               swap(cur3, cur4);             }             if (!used[cur3][cur4]) {               ++cur2;               used[cur3][cur4] = true;             }           }         }       }       ans = max(ans, cur2);     }     cout << ans << endl;   }   