import java.util.Scanner;
public class Binary
{
    public static void main (String[]args){
    int n;
    int counter = 1;
    Scanner scan = new Scanner(System.in);

    System.out.println ("Please a sequence of 1's and 0's");
    n= scan.nextInt();

    for (int index = 0; index < n.length();
    index++) {
    char aChar = n.charAt(index);
    }

    if (n < 0 || n > 1) {        //base case
        System.out.println ("Error. Please enter 1 or 0");
        n = scan.nextInt();}
    else if (n < 2){  //base case
        System.out.print(n);
        return;}
    else {
        n = (n/2);   //recursive step
        int answer = n%2;
        System.out.print(answer);}

}
}