用for循环判断输入的数是不是质数

2025-02-23 19:14:57
推荐回答(1个)
回答1:

import java.util.*;
public class Prime{
    public static void main(String[] args)
    { 
        Scanner reader = new Scanner(System.in);
        System.out.println("Input a number:");
        int num1= reader.nextInt();
        if (num1==2)
            System.out.println(num1+" is a prime number.");
        if (num1!=2){
            for(int i=2;i<=num1;i++){
                int remainder=num1%i;
                if (remainder==0){
               System.out.println(num1+" is not a prime number.");
                    break;
                }
                if(i==(num1-1)){
                   System.out.println(num1+" is a prime number.");
                    break;
                }  
            }
        }
    }
}