func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     int n;     cin >> n;     int t;     cin >> t;     for (int i = 0; i < n; ++i) {       int a, b;       cin >> a >> b;       int d[7] = {0};       d[a] = 1;       d[7 - a] = 1, d[b] = 1, d[7 - b] = 1;       d[t] = 1;       int cn = 0;       for (int j = 1; j < 7; ++j) {         if (d[j] == 0) {           t = 7 - j;           cn++;         }       }       if (cn == 2) return (cout <<  NO , 0);     }     cout <<  YES ;     return 0;   }   