[JUNGOL : 1309] 재귀 - 팩토리얼 [C/C++]

#include <stdio.h>
#include <stdlib.h>
 
unsigned long long recursive(int a){
 
    if(a == 1){
        printf("1! = 1\n");
        return 1;
    }
 
    else{
        printf("%d! = %d * %d!\n",a,a,a-1);
        return a * recursive(a-1);
    }
 
}
 
int main(void){
 
    int a;
    scanf("%d", &a);
 
    unsigned long long z = recursive(a);
 
    printf("%lld",z);
}