P. 57 Ex. 5

// Shavit Borisov
// CW

import java.util.Scanner;

public class Treasure {

    public static void main(String[] args)

    {
        Scanner in = new Scanner(System.in);

        final int SIZE = 50;
        int[] arr = new int[SIZE];
        // array needs to be initialized with correct order.

        int next = 0;

        int current = in.nextInt();

        while(next != -1)
        {
            next = arr[current];
            if(next == -1)
                break;
            arr[next] = current;
        }
        System.out.print(current);

        in.close();
    }
}