简易的加减乘除计算器

 1 package com.lin.method;
 2 
 3 import java.util.Scanner;
 4 
 5 public class Demo6 {
 6     public static void main(String[] args) {
 7         Scanner scanner = new Scanner(System.in);
 8         double num1 = scanner.nextDouble();
 9         String formula = scanner.next();
10         double num2 = scanner.nextDouble();
11         switch (formula) {
12             case "+":
13                 System.out.println(num1+num2);
14                 break;
15             case "-":
16                 System.out.println(num1-num2);
17                 break;
18             case "*":
19                 System.out.println(num1*num2);
20                 break;
21             case "/":
22                 System.out.println(num1/num2);
23                 break;
24         }
25         scanner.close();
26     }
27 }