1.2.1

Test/src/Computer.java

@@ -1,2 +1,63 @@
+import java.util.Scanner;
+
 public class Computer {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+
+        System.out.println("请输入第一个数字:");
+        double num1 = scanner.nextDouble();
+
+        System.out.println("请输入第二个数字:");
+        double num2 = scanner.nextDouble();
+
+        System.out.println("请选择操作 (+, -, *, /):");
+        String operation = scanner.next();
+
+        double result;
+        switch (operation) {
+            case "+":
+                result = add(num1, num2);
+                break;
+            case "-":
+                result = subtract(num1, num2);
+                break;
+            case "*":
+                result = multiply(num1, num2);
+                break;
+            case "/":
+                if (num2 != 0) {
+                    result = divide(num1, num2);
+                } else {
+                    System.out.println("除数不能为零!");
+                    return;
                 }
+                break;
+            default:
+                System.out.println("无效的操作符!");
+                return;
+        }
+
+        System.out.printf("%.2f %s %.2f = %.2f\n", num1, operation, num2, result);
+    }
+
+    // 加法
+    public static double add(double a, double b) {
+        return a + b;
+    }
+
+    // 减法
+    public static double subtract(double a, double b) {
+        return a - b;
+    }
+
+    // 乘法
+    public static double multiply(double a, double b) {
+        return a * b;
+    }
+
+    // 除法
+    public static double divide(double a, double b) {
+        return a / b;
+    }
+}
+