[Question] 9. Number of palindrome-give you an integer x, if x is a palindrome integer, return true; otherwise, return false.

Topic: 9. Number of palindrome

Give you an integer x, if x is a palindrome integer, return true; otherwise, return false.

The palindrome number refers to the same integer in both positive order (from left to right) and reverse order (from right to left). For example, 121 is a palindrome, but 123 is not.

answer

bool isPalindrome(int x)
{
    
    
    if(x<0)
        return false;
    // x是几位数，则temp就为几位数
    int temp=1;
    while(x/temp>=10)
    {
    
    
        temp*=10;
    }
    while(x>0)
    {
    
    
        //获取x左边的第一位
        int left=x/temp;
        //获取x的最后一位
        int right=x%10;
        //比较两位是否相同
        if(left!=right)
        {
    
    
            return false;
        }
        //将x已比较的第一位和最后一位去掉
        x=x%temp/10;
        //x变化，temp也必须变，以便获取第一位	
        temp/=100;
    }
    return true;
}