69 lines
1.7 KiB
Python
69 lines
1.7 KiB
Python
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def is_palindrome(num):
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"""
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判断一个整数是否是回文数
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参数:
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num (int): 要检查的整数
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返回:
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bool: 如果是回文数返回True，否则返回False
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"""
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if num < 0:
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return False
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str_num = str(num)
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return str_num == str_num[::-1]
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def find_palindromes_in_range(start, end):
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"""
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查找指定范围内的所有回文数
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参数:
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start (int): 起始值（包含）
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end (int): 结束值（包含）
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返回:
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list: 范围内的回文数列表
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"""
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palindromes = []
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for num in range(start, end + 1):
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if is_palindrome(num):
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palindromes.append(num)
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return palindromes
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def main():
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"""主函数，演示回文数计算"""
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print("回文数计算示例")
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print("=" * 30)
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# 测试一些数字
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test_numbers = [121, 123, 12321, -121, 0, 1, 10, 11, 1221]
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for num in test_numbers:
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result = is_palindrome(num)
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print(f"{num} 是回文数吗？{result}")
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print("\n查找 1 到 200 之间的回文数:")
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palindromes = find_palindromes_in_range(1, 200)
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print(f"共找到 {len(palindromes)} 个回文数:")
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print(palindromes)
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# 用户输入示例
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print("\n" + "=" * 30)
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try:
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user_input = input("请输入一个整数检查是否是回文数 (按Enter跳过): ")
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if user_input.strip():
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num = int(user_input)
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if is_palindrome(num):
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print(f"{num} 是回文数！")
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else:
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print(f"{num} 不是回文数。")
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except ValueError:
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print("输入无效，请输入一个整数。")
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except EOFError:
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pass # 脚本运行而非交互时可能发生
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if __name__ == "__main__":
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main()
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