View Compilation Error

0_0_24796850_5694.c: In function 'C':
0_0_24796850_5694.c:7:2: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
  for (int i = m + 1; i <= n; i++) ans *= i;
  ^
0_0_24796850_5694.c:7:2: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_24796850_5694.c:8:11: error: redefinition of 'i'
  for (int i = 1; i <= n-m; i++) ans /= i;
           ^
0_0_24796850_5694.c:7:11: note: previous definition of 'i' was here
  for (int i = m + 1; i <= n; i++) ans *= i;
           ^
0_0_24796850_5694.c:8:2: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
  for (int i = 1; i <= n-m; i++) ans /= i;
  ^