Java 排列与组合程序

编写一个Java程序，使用示例查找给定值的排列和组合。此程序接受n和r值，并使用数学公式计算排列和组合。

排列 = n! / (n – r)!

组合 = n! / ((n – r)! * r!)

更多 Java 程序 >> 点击此处。

package SimpleNumberPrograms;

import java.util.Scanner;

public class Permutations {

	private static Scanner sc;
	
	public static void main(String[] args) {
		
		sc = new Scanner(System.in);
		int n, r, NCR, NPR;
		
		System.out.print("Please Enter n Value = ");
		n = sc.nextInt();
		System.out.print("Please Enter r Value = ");
		r = sc.nextInt();
		
		NCR = fact(n)/(fact(n - r) * fact(r));
		NPR = fact(n)/fact(n - r);
		
		System.out.println("NCR Value = " + NCR);
		System.out.println("NPR Value = " + NPR);
	}
	
	public static int fact(int number) {
		if(number == 0 || number == 1) {
			return 1;
		}
		else {
			return number * fact(number - 1);
		}
	}
}