View Compilation Error

0_0_23752044_16254.c: In function 'main':
0_0_23752044_16254.c:19:4: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
    for (int j = 1; j < n - i; j++)
    ^
0_0_23752044_16254.c:19:4: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code