Palindrome Number(LeetCode)

Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.

Example 1:

Input: 121
Output: true

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.

Example 3:

Input: 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.

Follow up:

Coud you solve it without converting the integer to a string?

找回文数。要求不转化成字符串。

思路:

1.负数都不是

2.0是

3.将这个数倒序,核心就是取余,取商。不要忘了最后商为0 时还有一个余数要加上。

class Solution {
public:
	bool isPalindrome(int x) {
		if(x==0)
			return true;
		if(x<0)
			return false;
		int remainder = x%10;
		int quotient = x/10;
		int temp = 0;
		while(quotient){
			temp=temp*10+remainder;
			remainder = quotient%10;
			quotient = quotient/10;
		}
		temp=temp*10+remainder;
		if(temp==x)
			return true;
		return false;
	}
};

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转载自blog.csdn.net/u014485485/article/details/80308393