import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Horsemeet {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        String[] a = br.readLine().split(" ");
        String[] b = br.readLine().split(" ");

        int x1 = Integer.parseInt(a[0]);
        int y1 = Integer.parseInt(a[1]);
        int x2 = Integer.parseInt(b[0]);
        int y2 = Integer.parseInt(b[1]);

        System.out.println((x1+y1+x2+y2)%2!=0 ? "white" : "black");

        br.close();
    }
}