"负回文数失败"

Question

i need to determine if a number is palindrome or not ex: 121 yes, ex: -121 no. the program seems to work with palindrome numbers however i am having trouble figuring out the negative numbers, and non palindrome numbers

class Solution {
public:
    bool isPalindrome(int x) {
        int reverse = 0;
        int digit;
        int n = x;
        bool t = true;
         while(x > 0){
             digit = x%10;
             reverse = (reverse*10) + digit;
             x = x/10;  
         }
        if (n == reverse) {
         return t;
        } 
        else if(n != reverse) {
            return -1;
        }
    return -1;
         
    }
};

Answer 1

bool isPalindrome(int A)
{
int Rev{ 0 } , rem , C{ A };

while( ( abs( A ) ) ! = 0 )
{
rem = ( abs( A ) ) % 10;
Rev = Rev * 10 + rem;
A / = 10;
}

if( C ! = Rev or C < 0)
 return false;

else if( C == Rev and C > 0)
 return true;
}

Change your if statements with the following and then this works for negative numbers.

Hope this works for you!!

Answer 2

class Solution {
  public boolean isPalindrome(int x){
    int reverse=0;
  int duplicate_x=x;
    for(int i=0;i<=x;i++)
       {
      int r=x%10;
      reverse=(reverse*10)+r;
      x=x/10;
        }
        if(x>=1){       **wrote this if condition to catch  unit place number**
         reverse=(reverse*10)+x;
        }
         if(reverse==duplicate_x)
            {
              return true;
             }
            else
            {
           return false; 
            }
          }
}

I used for loop because I was getting time exceeding error in leetcode and has you mention in your question about negative number palindrome I don't get it why should we write code for those negative number palindrome where we know a **negative number cannot be a palindrome number! Please correct me if I am wrong

Answer 3

int x=121;
    if(x<0){
        System.out.println("false");
        System.exit(0); 
    }
    int div, sum=0;
    int res=x;
    while(x!=0){
        div = x%10;
        sum = sum*10 + div;
        x=x/10;
    }
    if(sum==res)
        System.out.println("True");

Can't be able to come up with a simple solution more than this one.