View Compilation Error

0_0_19650921_19331.c: In function 'dfs':
0_0_19650921_19331.c:18:5: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
     for (int k = 0; k<4; k++)
     ^
0_0_19650921_19331.c:18:5: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_19650921_19331.c: In function 'main':
0_0_19650921_19331.c:37:9: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
         for (int i = 1; i<=n; i++)
         ^
0_0_19650921_19331.c:40:13: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
             for (int j = 1; j<=m; j++)
             ^