Java简单计算器实现步骤详解

import java.util.Scanner;
public class SimpleCalculator {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
    System.out.print("请输入第一个数字: ");
    double num1 = scanner.nextDouble();

    System.out.print("请输入运算符 (+, -, *, /): ");
    char operator = scanner.next().charAt(0);

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

    double result = 0;
    boolean validOperator = true;

    switch (operator) {
        case '+':
            result = num1 + num2;
            break;
        case '-':
            result = num1 - num2;
            break;
        case '*':
            result = num1 * num2;
            break;
        case '/':
            if (num2 == 0) {
                System.out.println("错误：除数不能为零！");
                validOperator = false;
            } else {
                result = num1 / num2;
            }
            break;
        default:
            System.out.println("不支持的运算符: " + operator);
            validOperator = false;
    }

    if (validOperator) {
        System.out.printf("%.2f %c %.2f = %.2f%n", num1, operator, num2, result);
    }

    scanner.close();
}
}