【C语言程序设计第四版】例10-3, 10-4代码

#include <stdio.h>
int gcd(int m, int n);
void reverse(int num);
int main(void){
    
    int m, n;
    
    scanf("%d", &m);
    reverse(m);
    
//    scanf("%d%d",&m, &n);
//    printf("%d", gcd(m, n));
    
    return 0;
}

int gcd(int m ,int n){
    
    if (m % n == 0) {
        return n;
    }else{
        return gcd(n, m%n);
    }
}


void reverse(int num){
    if (num <= 9) {
        printf("%d", num);
    }else{
        printf("%d", num%10);
        reverse(num /10);
    }
}