實現兩個數之間的加，減，乘，除

package com.wu.method;
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import java.util.Scanner;
​
public class TestDemo {
  //實現兩個數之間的加，減，乘，除！！！
  public static void main(String[] args) {
    //new一個scanner互動物件
    Scanner scanner = new Scanner(System.in);
​
    System.out.println("輸入你要計算的數字1：");
    double num1 = scanner.nextDouble();
​
    System.out.println("輸入你要進行什麼運算：");
    String operator = scanner.next();
​
    System.out.println("輸入你要計算的數字2：");
    double num2 = scanner.nextDouble();
​
    //賦值給result
    double result = 0;
​
    //用switch結構判斷加，減，乘，除！！！！！！
    switch (operator){
      case "+":
        result = num1+num2;
        break;
      case "-":
        result = num1-num2;
        break;
      case "*":
        result = num1*num2;
        break;
      case "/":
        result = num1/num2;
        break;
      default:
        System.out.println("輸入不合法");
     }
    System.out.println("你要計算的式子為"+num1+operator+num2+"="+result);
​
​
​
    scanner.close();
   }
}