开学日记2

今天我写了一个简单的计算器程序，能够执行加法、减法、乘法和除法。程序代码如下：

import java.util.Scanner;

public class Calculator {

public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    System.out.print("Enter first number: ");
    double num1 = scanner.nextDouble();
    System.out.print("Enter second number: ");
    double num2 = scanner.nextDouble();

    System.out.println("Choose an operation: +, -, *, /");
    char operator = scanner.next().charAt(0);
    double result;

    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.printf("Error! operator is not correct");
            return;
    }
    System.out.printf("%.1f %c %.1f = %.1f", num1, operator, num2, result);
}

}