A simple calculator

public class Calculator {

	public static void main(String[] args) {
		System.out.println("欢迎使用简单的计算器！");
		System.out.print("请输入第一个数字：");
		java.util.Scanner s = new java.util.Scanner(System.in);
		double num1 = s.nextDouble();
		System.out.print("请输入运算符:");
		String operator = s.next();
		System.out.print("请输入第二个数字：");
		double num2 = s.nextDouble();
		double result = 0;
		switch (operator) {
		case "+":
			result = num1 + num2;
			break;
		case "-":
			result = num1 - num2;
			break;
		case "*":
			result = num1 * num2;
			break;
		case "/":
			result = num1 / num2;
			break;
		case "%":
			result = num1 % num2;
			break;
		}
		System.out.println("计算结果为：" + num1 + operator + num2 + "=" + result);


	}

}