Someone enters a string and check whether is it palindrome or not,which logic is used? code example

Example 1: reads the string in then determines if the string is a palindrome.

#include <iostream>
using namespace std;
 
// Iterative function to check if given string is a palindrome or not
bool isPalindrome(string str)
{
    int low = 0;
    int high = str.length() - 1;
 
    while (low < high)
    {
        // if mismatch happens
        if (str[low] != str[high])
            return false;
 
        low++;
        high--;
    }
 
    return true;
}
 
int main()
{
    string str = "XYXYX";
 
    if (isPalindrome(str))
        cout << "Palindrome";
    else
        cout << "Not Palindrome";
 
    return 0;
}

Example 2: Write a program to check whether inputted string is palindrome or not.

#include <stdio.h>
#include <string.h>
 
int main()
{
    char s[1000];  
    int i,n,c=0;
 
    printf("Enter  the string : ");
    gets(s);
    n=strlen(s);
 
    for(i=0;i<n/2;i++)  
    {
    	if(s[i]==s[n-i-1])
    	c++;
 
 	}
 	if(c==i)
 	    printf("string is palindrome");
    else
        printf("string is not palindrome");
 
 	 
     
    return 0;
}