View Compilation Error

0_0_37439317_18627.c: In function 'main':
0_0_37439317_18627.c:7:2: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
  for (int n = 0; n != T; n++) {
  ^
0_0_37439317_18627.c:7:2: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_37439317_18627.c:9:3: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
   for (int s = 1; s <= a; s++) {
   ^