LeetCode 9. Palindrome Number（c语言版）

题目：

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?

 

代码：

bool isPalindrome(int x) {
    if(x<0) return false;
    if(x==0) return true;
    int a[100],i,j,sum;
    for(i=0;x!=0;i++)
    {
        a[i]=x%10;
        x/=10;
    }
    sum=i;
    i--;
    if(a[0]==0) return false;
    for(j=0;j<sum/2;j++,i--)
        if(a[j]!=a[i]) return false;
    return true;
}