View Compilation Error

0_0_30391038_12897.c: In function 'main':
0_0_30391038_12897.c:11:9: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
         for(int j = 1; j <= n/2; j++)
         ^
0_0_30391038_12897.c:11:9: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_30391038_12897.c:23:5: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
     for(int j = 0; j < i; j++)
     ^