Question

import java.util.Scanner;
public class Calculator 
{
    public static void main(String args[])
    {
        System.out.println("Enter the numbers only ");
        Scanner num =new Scanner(System.in);
        System.out.println("Enter the number of times you want to run loop ");  
        Scanner loop =new Scanner(System.in);
        int n =loop.nextInt();
        while(n!=0)
        {
            System.out.println("Enter the Cases  1 for addition,2 for Subtraction,3 for Division 4 for multipication and 5 for reaminder  ");   
            Scanner cas =new Scanner(System.in);
            int c = cas.nextInt();
            double calc,first,second;
            switch (c)
            {
            case 1:
                System.out.println("addition of two number is ");
                first = num.nextDouble(); 
                second=num.nextDouble();
                calc = first + second;
                System.out.println(calc);
                break;
            case 2:
                System.out.println("subtraction of two number is ");
                first = num.nextDouble(); 
                second = num.nextDouble();
                calc = first - second;      
                System.out.println(calc);
                break;
            case 3:
                System.out.println("division of two number is ");
                first = num.nextDouble(); 
                second = num.nextDouble();
                calc = first / second;
                System.out.println(calc);
                break;
            case 4:
                System.out.println("multipication of two number is ");
                first = num.nextDouble(); 
                second = num.nextDouble();
                calc = first * second;
                System.out.println(calc);
                break;  
            case 5:
                System.out.println("remainder of two number is ");
                first = num.nextDouble(); 
                second = num.nextDouble();
                calc = first % second;
                System.out.println(calc);
                break;  
            default:
                System.out.println("you did not enter 1,2,3,4,5 you entered something else ");
            }
        n--;
        }
        System.out.println("the program has end, THANK YOU!!"); 
    }
}

这是通过询问用户输入来计算的java代码。如何在此代码中对所有计算使用相同的数字？它每次都询问用户新的数字，但我希望此代码仅通过一个输入进行所有计算。

Answer 1

您需要致电

 first = num.nextDouble(); 
 second = num.nextDouble();

只有一次。在您希望用户输入数字的位置调用它。

对于您的示例，您应将其更改为：

import java.util.Scanner;
public class Calculator 
{
    public static void main(String args[])
    {
        System.out.println("Enter the numbers only ");
        Scanner num =new Scanner(System.in);
        double first,second;
        first = num.nextDouble();  //Get first number
        second = num.nextDouble(); //Get second number
        System.out.println("Enter the number of times you want to run loop     ");  
        Scanner loop =new Scanner(System.in);
        int n =loop.nextInt();
        while(n!=0)
        {
            System.out.println("Enter the Cases  1 for addition,2 for     Subtraction,3 for Division 4 for multipication and 5 for reaminder  ");   
            Scanner cas =new Scanner(System.in);
            int c = cas.nextInt();
            double calc;
            switch (c)
            {
            case 1:
                System.out.println("addition of two number is ");
                calc = first + second;
                System.out.println(calc);
                break;
            case 2:
                System.out.println("subtraction of two number is ");
                calc = first - second;      
                System.out.println(calc);
                break;
            case 3:
                System.out.println("division of two number is ");
                calc = first / second;
                System.out.println(calc);
                break;
            case 4:
                System.out.println("multipication of two number is ");
                calc = first * second;
                System.out.println(calc);
                break;  
            case 5:
                System.out.println("remainder of two number is ");
                calc = first % second;
                System.out.println(calc);
                break;  
            default:
                System.out.println("you did not enter 1,2,3,4,5 you entered     something else ");
            }
        n--;
        }
        System.out.println("the program has end, THANK YOU!!"); 
    }
}

Answer 2

如果删除

中断;

从每个案例开始，每个案例都会从用户选择的案例开始

这是你想要的吗？

如何在所有计算中使用相同的数字

2 个答案: