View Compilation Error

0_0_15985347_9118.c: In function 'main':
0_0_15985347_9118.c:19:9: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
         for (int i = 0; i < n; ++i) {
         ^
0_0_15985347_9118.c:19:9: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_15985347_9118.c:20:13: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
             for (int j = 0; j < m; ++j) {
             ^