Replace palindrome function with multiply and divide operations

- Add multiply() function for multiplication
- Add divide() function with zero divisor check
- Add comprehensive test cases and interactive mode
- Remove palindrome detection functionality

math.py

@@ -1,70 +1,155 @@
 #!/usr/bin/env python3
 """
-math.py - 判断回文数的脚本
+math.py - 数学运算工具
+提供乘法和除法运算功能
 """
 
-def is_palindrome(n: int) -> bool:
+def multiply(a: float, b: float) -> float:
     """
-    判断一个整数是否是回文数。
+    计算两个数的乘积
 
     参数:
-        n: 要检查的整数
+        a: 第一个数
+        b: 第二个数
 
     返回:
-        如果是回文数返回True，否则返回False
+        两个数的乘积
     """
-    if n < 0:
-        return False
-    if n == 0:
-        return True
-
-    # 转换为字符串并检查是否等于反转后的字符串
-    str_n = str(n)
-    return str_n == str_n[::-1]
+    return a * b
 
 
-def main():
-    """测试函数"""
-    test_cases = [
-        121,      # True
-        12321,    # True
-        123,      # False
-        1221,     # True
-        123321,   # True
-        1234321,  # True
-        12344321, # True
-        10,       # False
-        0,        # True
-        -121,     # False
-        123456,   # False
-        123454321,# True
+def divide(a: float, b: float) -> float:
+    """
+    计算两个数的除法
+
+    参数:
+        a: 被除数
+        b: 除数
+
+    返回:
+        除法结果
+
+    异常:
+        ValueError: 当除数为0时抛出
+    """
+    if b == 0:
+        raise ValueError("除数不能为0")
+    return a / b
+
+
+def test_operations():
+    """测试乘法和除法运算"""
+    print("测试乘法运算:")
+    print("-" * 30)
+
+    # 测试乘法
+    test_cases_multiply = [
+        (2, 3, 6),
+        (0, 5, 0),
+        (-3, 4, -12),
+        (2.5, 4, 10.0),
+        (-2.5, -4, 10.0),
+        (0, 0, 0),
     ]
 
-    print("测试回文数判断函数:")
-    print("-" * 40)
-    for num in test_cases:
-        result = is_palindrome(num)
-        print(f"{num:12} -> {'是回文数' if result else '不是回文数'}")
+    for a, b, expected in test_cases_multiply:
+        result = multiply(a, b)
+        status = "✓" if abs(result - expected) < 1e-10 else "✗"
+        print(f"{a} × {b} = {result} {status} (期望: {expected})")
 
-    # 额外测试：用户输入
+    print("\n测试除法运算:")
+    print("-" * 30)
+
+    # 测试除法
+    test_cases_divide = [
+        (6, 2, 3),
+        (10, 4, 2.5),
+        (-12, 3, -4),
+        (0, 5, 0),
+        (7.5, 2.5, 3),
+        (-10, -2, 5),
+    ]
+
+    for a, b, expected in test_cases_divide:
+        try:
+            result = divide(a, b)
+            status = "✓" if abs(result - expected) < 1e-10 else "✗"
+            print(f"{a} ÷ {b} = {result} {status} (期望: {expected})")
+        except ValueError as e:
+            print(f"{a} ÷ {b} = 错误: {e}")
+
+    # 测试除数为0的情况
+    print("\n测试除数为0的情况:")
+    print("-" * 30)
+    zero_test_cases = [
+        (5, 0),
+        (0, 0),
+        (-3, 0),
+        (10.5, 0),
+    ]
+
+    for a, b in zero_test_cases:
+        try:
+            result = divide(a, b)
+            print(f"{a} ÷ {b} = {result} ✗ (应该抛出异常)")
+        except ValueError as e:
+            print(f"{a} ÷ {b} = 正确抛出异常: {e}")
+
+
+def interactive_mode():
+    """交互式模式"""
     print("\n" + "=" * 40)
-    print("手动测试模式 (输入 'exit' 退出)")
+    print("交互式计算模式 (输入 'exit' 退出)")
     print("=" * 40)
 
     while True:
-        user_input = input("请输入一个整数: ").strip()
-        if user_input.lower() == 'exit':
-            print("程序结束。")
+        print("\n选择操作:")
+        print("1. 乘法")
+        print("2. 除法")
+        print("exit. 退出")
+
+        choice = input("请选择 (1/2/exit): ").strip().lower()
+
+        if choice == 'exit':
+            print("退出交互模式。")
             break
 
+        if choice not in ['1', '2']:
+            print("无效选择，请重新输入。")
+            continue
+
         try:
-            num = int(user_input)
-            if is_palindrome(num):
-                print(f"{num} 是回文数。")
-            else:
-                print(f"{num} 不是回文数。")
+            a = float(input("请输入第一个数: "))
+            b = float(input("请输入第二个数: "))
+
+            if choice == '1':
+                result = multiply(a, b)
+                print(f"{a} × {b} = {result}")
+            elif choice == '2':
+                try:
+                    result = divide(a, b)
+                    print(f"{a} ÷ {b} = {result}")
+                except ValueError as e:
+                    print(f"错误: {e}")
+
         except ValueError:
-            print("错误：请输入有效的整数。")
+            print("错误：请输入有效的数字。")
+
+
+def main():
+    """主函数"""
+    print("数学运算工具测试")
+    print("=" * 40)
+
+    # 运行测试
+    test_operations()
+
+    # 询问是否进入交互模式
+    choice = input("\n是否进入交互式计算模式? (y/n): ").strip().lower()
+    if choice == 'y':
+        interactive_mode()
+    else:
+        print("程序结束。")
 
 
 if __name__ == "__main__":