Question

我想写一个用户给出的数字总和。如果用户说第一个数字是1而第二个数字是5，那么应该在程序“1 + 2 + 3 + 4 + 5 = 15”上写入。我管理的结束总和为“15”，但我无法打印出如“1 + 2 + 3 + 4 + 5”这样的行。请帮帮我。

import javax.swing.JOptionPane;

public class Oppgave2{

    public static void main(String[] args){

    int x;
    int y;
    String i, j;

    i = JOptionPane.showInputDialog("Write begining number:");
    x = Integer.parseInt(i);
    j = JOptionPane.showInputDialog("Write end number:");
    y = Integer.parseInt(j);

    if ( x > y || x == y){

    i = JOptionPane.showInputDialog("Wrong! 
    Begining number is bigger or same as end number!
    \nTry again! Write begining number:");

    x = Integer.parseInt(i);
    j = JOptionPane.showInputDialog("Write end number:");
    y = Integer.parseInt(j);
}

int number;

number = x;

int sum = 0;

while(number <= y){

    sum = sum + number;
    number++;
}

// Here or in while it should write OptionPane.showMessageDialog(null, "1+2+3+4+5 "  + sum);


    JOptionPane.showMessageDialog(null, "the sum is: "  + sum);

    }
}

Answer 1

创建一个字符串并像这样添加：

int number;

number = x;

int sum = 0;

//Message used for the sum, in the form of "1+2+3+4..."
String sumMessage = "";

while(number <= y){
    //Append the number and then "+" to sumMessage.
    sumMessage = sumMessage + number + "+";
    sum = sum + number;
    number++;
}
//Remove the final + in the sumMessage using substring.
sumMessage = sumMessage.substring(0, sumMessage.length() - 1);

// Here or in while it should write OptionPane.showMessageDialog(null, "1+2+3+4+5 "  + sum);


JOptionPane.showMessageDialog(null, sumMessage + " is: "  + sum);

总结用户输入的一系列数字，同时显示求和过程

1 个答案: