func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     long long n;     cin >> n;     long long x, a, b, i, f = 1, pa, push_back;     vector<pair<long long, long long> > v(n);     vector<long long> ch;     cin >> x;     cin >> a >> b;     pa = a, push_back = b;     if (a + b == 7) f = 0;     for (i = 1; i < n; i++) {       cin >> a >> b;       if (f == 1) {         if (a + b != 7) {           if (a == pa || a == 7 - pa || a == push_back || a == 7 - push_back) {             if (b == pa || b == 7 - pa || b == push_back || b == 7 - push_back) {               f = 1;             } else               f = 0;           } else             f = 0;         } else           f = 0;       }       pa = a, push_back = b;     }     if (f == 1) {       cout <<  YES  << endl;     } else {       cout <<  NO  << endl;     }   }   