func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     int n, m, k;     cin >> n >> m >> k;     int r = m * n - 2 * (k - 1);     cout << r <<    ;     int i = 0, j = 0;     for (; i < n; i++) {       if (i % 2 == 0) {         for (j = 0; j < m; j++) {           cout << i + 1 <<     << j + 1 <<    ;           r--;           if (r == 0) break;         }       } else {         for (j = m; j > 0; j--) {           cout << i + 1 <<     << j <<    ;           r--;           if (r == 0) break;         }       }       if (r == 0) break;     }     if (i % 2 == 0) {       if (j != m)         j++;       else         i++;     } else {       if (j != 0)         j--;       else         i++;     }     cout << endl;     r = 2;     for (; i < n; i++) {       if (i % 2 == 0) {         for (; j < m; j++) {           if (r == 2) cout << r <<    ;           cout << i + 1 <<     << j + 1 <<    ;           r--;           if (r == 0) {             cout << endl;             r = 2;           }         }       } else {         for (; j > 0; j--) {           if (r == 2) cout << r <<    ;           cout << i + 1 <<     << j <<    ;           r--;           if (r == 0) {             cout << endl;             r = 2;           }         }       }       if (r == 0) r = 2;     }     return 0;   }   