Question

使用while循环不断询问用户输入的顺序直到用户确实以正确的顺序给出两个数字（第一个小于第二

嗨！我是java的初学者，我有这个代码，但我无法循环“错误”消息。它只打印2次

import java.util.Scanner;

public class Q6 {
    public static void main(String[] args) {
        int num1, num2;
        Scanner keyboard = new Scanner(System.in);
        System.out.print("Please type two numbers:");
        num1 = keyboard.nextInt();
        num2 = keyboard.nextInt();

        if (num1 < num2) {
            int counter = num1;
            while (counter <= num2) {
                System.out.print(counter + " ");
                counter = counter + 1;
            }
        } 
        else {
            System.out.println("Error: the first number must be smaller than the second");
            System.out.print("Please type two numbers: ");
            num1 = keyboard.nextInt();
            num2 = keyboard.nextInt();
        }
    }
}

Answer 1

int num1,num2;
while (num1>=num2) {
    Scanner keyboard = new Scanner(System.in);
    System.out.println("Please type two numbers");
    System.out.printn("first number must be smaller than the second:)";
    num1 = keyboard.nextInt();
    num2 = keyboard.nextInt();
}

Answer 2

int num1,num2;
while (num1>=num2) {
    Scanner keyboard = new Scanner(System.in);
    System.out.println("Please type two numbers:");
    num1 = keyboard.nextInt();
    num2 = keyboard.nextInt();
    if(num1>=num2) {
         System.out.println("Error: First number must be smaller than the second.");
    }
}

循环使用Java代码的问题

2 个答案: