// this function will return 1 if the string sent in arguments is palindrome //else it will return 0
int palindrome(int start_of_string, int end_of_string, string &strr)
{
// base case to check if the string is not empty
if (start_of_string>= end_of_string)
return 1;
if (strr[start_of_string] != strr[end_of_string])
return 0;
// recursive call
return palindrome(++start_of_string, --end_of_string, strr);
}