java - 如何在 java 中使用用户输入结束程序？

Question

我目前无法通过用户输入结束我的程序。例如，我现在只能在用户输入 20 个数字时结束。我想要它做的是，如果用户输入的数字超过 100，它应该停止程序并显示直方图以及一个数字来显示用户每次输入数字的次数。对不起，如果我没有任何意义，如果需要任何进一步的信息，我会更新这篇文章。这是我的代码。

import java.util.Scanner;

public class Marks {
    /**
    * @param args the command line arguments
    */
    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);

        int[] array = new int[23];
        int num = 0;
        int count = 0;
        int total = 0;

        System.out.println ("Enter students marks in the range 0 to 100\n");

        for (count = 0; count <= 20; count++)
        {
            System.out.println ("Enter a number:");
            num = scan.nextInt();
            while (num < 0 || num > 100)
            {
                System.out.println ("Invalid number. Enter a valid number.");
                num = scan.nextInt();
            }
            array[count] = num;
           total=count;
        }
        System.out.println ("How many times a number between 0-100 occur.");

        String[] asterisk = {"0- 29   | ", "30- 39  | ","40- 69  | ", "70- 100 | "}; //4 strings

        for (count = 0; count <= 20; count++)
        {
            num=array[count];
            if (num <=29) asterisk [0] +="*";
            else if (num <=39) asterisk[1] +="*";
            else if (num <=69) asterisk[2] +="*";
            else if (num <=100) asterisk[3] +="*";
        }
        for (count =0;count < 4;count++)
            System.out.println(asterisk[count]);
        System.out.println("The total amount of students is " + total);
    }
}

Answer 1

当用户交互时，你可以写

System.exit(0);