标签：10 return Python 121 palindromeNum str 字符串 解法 回文
回文数就是指整数倒过来和原整数相等。
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Example 1:
Input: 121
Output: true
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Example 2:
Input: -121
Output: false
Explanation: From left to right, it reads -121. From right to left, it becomes 121-. Therefore it is not a palindrome.
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Example 3:
Input: 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.
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1：整数转字符串，通过下标对比确定该整数是否为回文数
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str_x = str(x)
for i in range(0,int(len(str_x)/2)):
if str_x[i] != str_x[-i-1]:
return False
return True
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2：字符串切片操作，str[index:index:step]，中括号里面分别为：字符起点、终点和步长
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str_x = str(x)
return str_x == str_x[::-1]
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3：数学计算的方法，对比反转整数的值
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if x<0:
return False
temp_x = x;
palindromeNum = 0
while temp_x != 0:
palindromeNum = palindromeNum*10 + temp_x%10
temp_x /= 10
return palindromeNum == x
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4：整数转字符串，反转字符串，对比反转后字符串与原字符串是否相等
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str_x = str(x)
str_y = ""
for i in str_x:
str_y = i + str_y
return str_y == str_x
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标签：10,
return,
Python,
121,
palindromeNum,
str,
字符串,
解法,
回文
From： https://www.cnblogs.com/chenxiaomeng/p/18032218