using System;

public class Program

{

    public static void Main()

    {

        var myArray = new int[]{1,2,34,4,3,25,342,23};

        var find  = Convert.ToInt32(Console.ReadLine());

        for(var i = 0;i < myArray.Length;i++){

            if(myArray[i] == find){

                Console.WriteLine("index = " + i);

                break;

            }

        }

    }

}