import java.util.Scanner;

public class calculator {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.print("请输入第一个数:");
        double num1 = scanner.nextDouble();

        System.out.print("请输入第二个数:");
        double num2 = scanner.nextDouble();

        System.out.print("请选择操作符 (+, -, *, /, %):");
        String operation = scanner.next();


}