View Compilation Error

0_0_24099919_8478.c: In function 'dfs':
0_0_24099919_8478.c:23:2: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
  for (int i = 0; i < n; i++) {
  ^
0_0_24099919_8478.c:23:2: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_24099919_8478.c: In function 'main':
0_0_24099919_8478.c:42:3: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
   for (int i = 0; i < n; i++) {
   ^