三十行代码实现一个简单计算器

代码很简单，直接上代码：

import java.util.Scanner;public class calc {public static void main(String args[]){calc();}public static double calc(){String operator;double numA,numB,result = 0;Scanner scanner = new Scanner(System.in);numA = scanner.nextDouble();numB = scanner.nextDouble();operator = scanner.next();switch (operator) {case "+":result = numA + numB;break;case "-":result = numA - numB;break;case "*":result = numA * numB;break;case "/":result = numA / numB;break;default:break;}System.out.println(result);return result;}}