[BOJ]10872번: 팩토리얼(java, c++)

https://www.acmicpc.net/problem/10872

10872번: 팩토리얼

 

 

1. bottom-up 방식

java 소스

import java.util.Scanner;
 
public class Main {
    public static void main(String[] args) {
 
        Scanner sc = new Scanner(System.in);
        
        int num = sc.nextInt();
        int result = 1;
        
        while(num-- > 0) {
            result *= num + 1;
        }
        
        System.out.println(result);
    }
}
 

 

c++소스

#include <iostream>
 
using namespace std;
 
int get_factorial(int num)
{
    if (num == 0)
    {
        return 1;
    }
 
    int sum = 1;
 
    for (int i = 1; i <= num; i++)
    {
        sum *= i;
    }
    
    return sum;
}
 
int main()
{
    // 입출력 향상
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
 
    int n;
    cin >> n;
 
    cout << get_factorial(n);
    
    return 0;
}

 

 

 

2. top-down방식 (재귀)

#include <iostream>
 
using namespace std;
 
int get_factorial(int num)
{
    if (num == 0)
    {
        return 1;
    }
    
    return num * get_factorial(num - 1);
}
 
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
 
    int n;
    cin >> n;
 
    cout << get_factorial(n);
    
    return 0;
}