What are lychrel numbers?

#include <iostream>
using namespace std;
int reverse(int num)
{
  int reversed = 0;
  while(num>0)
  {
    int mod = num%10;
    reversed = (reversed*10) + mod;
    num = num/10;
  }
  return reversed;
}
void isLychrel(int num, int max)
{
  //variable that holds 0 if lychrel and 1 if not
  int lychrel = 0;
  //duplicate the number for checking later
  int num_temp=num;
  while(num>0)
  {
    // get the reverse
    int palindrome = reverse(num);
    // compare with original
    if(palindrome == num)
    {
    // set the check to 1 and exit loop
      lychrel = 1;
      break;
    }
    // if not a palindrom, reverse the number and add to the original number
    num = reverse(num) + num;
    // decrease the iteration count
    max--;
  }
  // display results
  if(lychrel)
  {
    cout<< "The number "<<num_temp<<" is not lycheral."<<endl;
  }
  else
  {
    cout<< "The number "<<num_temp<<" is lycheral."<<endl;
  }
}
int main() {
  int max = 10;
  int num_1 = 35;
  int num_2 = 295;
  //check if the number is lychrel or not
  isLychrel(num_1, max);
  isLychrel(num_2, max);
  
 
}

Explanation

For the sake of implementation, the above code uses a maximum number to limit the iterations. If a palindrome is found within the limit, it is not lychrel.

The program is implemented for two numbers, 35 and 295.
The program calls the isLychrel function, which performs iterations until it finds a palindrome or reaches the maximum limit of iterations.
The isLychrel function calls the reverse function and compares the returned value with the original value to check if the original number is a palindrome or not.
If the number is not a palindrome, the program calls the reverse function again, adds the returned value to the original number, and repeats the process.

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What are lychrel numbers?

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Explanation