func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long MOD = 1000000007;   const int INF = 1e9;   const long long LINF = 1LL * INF * INF;   const int MAXN = 100007;   const double EPS = 1e-7;   int A[MAXN];   int main() {     ios_base::sync_with_stdio(0);     int n, m;     cin >> n >> m;     if (n == 1 && m == 1) {       cout <<  YES n1 ;       return 0;     }     if (n == 1 && m <= 3 || m == 1 && n <= 3 || n == 2 && m <= 3 ||         m == 2 && n <= 3) {       cout <<  NO ;       return 0;     }     if (n == 1 && m == 4) {       cout <<  YES n2 4 1 3 ;       return 0;     }     if (n == 4 && m == 1) {       cout <<  YES n2 n4 n1 n3 ;       return 0;     }     if (n == 2 && m == 4) {       cout <<  YES n ;       cout <<  5 4 7 2  << endl;       cout <<  3 6 1 8 ;       return 0;     }     if (n == 4 && m == 2) {       cout <<  YES n ;       cout <<  6 1 n ;       cout <<  3 8 n ;       cout <<  2 5 n ;       cout <<  7 4 n ;       return 0;     }     if (n == 3 && m == 3) {       cout <<  YES n ;       cout <<  2 9 4 n ;       cout <<  7 5 3 n ;       cout <<  6 1 8 n ;       return 0;     }     if (n == 3 && m == 4) {       cout <<  YES n ;       cout <<  6 8 11 2 n ;       cout <<  9 3 1 10 n ;       cout <<  4 12 7 5 n ;       return 0;     }     if (n == 4 && m == 3) {       cout <<  YES n ;       cout <<  10 3 9 n ;       cout <<  5 1 7 n ;       cout <<  12 6 11 n ;       cout <<  4 8 2 n ;       return 0;     }     if (n == 4 && m == 4) {       cout <<  YES n ;       cout <<  2 11 14 9 n ;       cout <<  16 6 8 1 n ;       cout <<  13 3 10 4 n ;       cout <<  7 5 12 15 n ;       return 0;     }     if (n >= 5) {       cout <<  YES n ;       for (int i = (0); i < (2); ++i) {         for (int f = i * m + 1; f <= n * m; f += 2 * m) {           for (int j = (1); j < (m + 1); ++j) {             int cur = f + j - 1;             if ((j + 1) & 1) cur += m;             if (cur > n * m) cur -= n * m;             cout << cur <<    ;           }           cout << endl;         }       }       return 0;     }     if (m >= 5) {       cout <<  YES n ;       for (int i = (1); i < (n + 1); ++i) {         int cur = 1;         for (int j = (1); j < (m + 1); ++j) {           int c = cur;           cur += 2;           if (cur > m) cur = 2;           if ((i + 1) & 1) ++c;           if (c > m) c -= m;           cout << (i - 1) * m + c <<    ;         }         cout << endl;       }       return 0;     }     return 0;   }   