using System;

public class Program

{

    public static void Main()

    {

        int a = 312;

        int b = 1354;

        a = a/10%10*10+a%10;

        b = b/10%10*10+b%10;

        int[] s = new int[2]{a, b};

        foreach(int item in s){

            //Console.WriteLine(item);

            if((int)Math.Floor((decimal)item/10) == item%10){

                Console.WriteLine(item/10);

            }

        }

    }

}