// print digits from an integer one per line, reverse order

#include <stdio.h>

// 1521 % 10 = R 1
// 1521/10 = 152 
// 152 % 10 = R 2
// 152/10 =  15
// 15 % 10 = R 5
// 15/10 =  1
//  1 % 10 = R 1

int main(int argc, char *argv[]) {
    int num;

    while (1) {  
        printf("Integer? ");
        if (scanf("%d", &num) != 1) break;

        // extract the digits
        do {
            printf("%d\n", num % 10);
            num = num / 10;
        } while (num != 0);
    }
    return 0;
}