func_code_string: #include <bits/stdc++.h>   using namespace std;   mt19937 rng((int)chrono::steady_clock::now().time_since_epoch().count());   char mat[105][105];   void solve() {     int n, m, horizontal;     cin >> n >> m >> horizontal;     int vertical = n * m / 2 - horizontal;     int oxe = 0, nte = 0;     char cc =  e ;     if (n % 2 != m % 2) {       if (n % 2 == 0) {         for (int i = 0; i < n; i += 2) {           mat[i][m - 1] = mat[i + 1][m - 1] = cc++;           if (cc >  z ) cc =  e ;         }         vertical -= n / 2;         m--;         nte = 1;       } else {         for (int j = 0; j < m; j += 2) {           mat[n - 1][j] = mat[n - 1][j + 1] = cc++;           if (cc >  z ) cc =  e ;         }         horizontal -= m / 2;         n--;         oxe = 1;       }     }     assert(n % 2 == 0 && m % 2 == 0);     int puth = n * m / 2;     int putv = 0;     char mofio[] = { a ,  b };     int cur = 0;     for (int i = 0; i < n; i++) {       for (int j = 0; j < m; j += 2) {         mat[i][j] = mat[i][j + 1] = mofio[cur];         cur ^= 1;       }       if (m % 4 == 0) cur ^= 1;     }     mofio[0] =  c , mofio[1] =  d ;     cur = 0;     for (int i = 0; i < n; i += 2) {       for (int j = 0; j < m; j += 2) {         if (puth == horizontal && putv == vertical) {           cout <<  YES n ;           for (int ii = 0; ii < n + oxe; ii++) {             for (int jj = 0; jj < m + nte; jj++) {               cout << mat[ii][jj];             }             cout <<   n ;           }           return;         }         mat[i][j] = mat[i + 1][j] = mofio[cur];         mat[i][j + 1] = mat[i + 1][j + 1] = mofio[cur ^ 1];         puth -= 2;         putv += 2;       }       cur ^= 1;     }     if (puth == horizontal && putv == vertical) {       cout <<  YES n ;       for (int ii = 0; ii < n + oxe; ii++) {         for (int jj = 0; jj < m + nte; jj++) {           cout << mat[ii][jj];         }         cout <<   n ;       }       return;     }     cout <<  NO n ;   }   int main() {     ios::sync_with_stdio(false);     cin.tie(0);     int tt;     cin >> tt;     while (tt--) {       solve();     }     return 0;   }   