#include <bits/stdc++.h>



int main()
{
    int wX, wY;
    int bX, bY;

    scanf("%d %d", &wX, &wY);
    scanf("%d %d", &bX, &bY);

    int dX = abs(wX - bX);
    int dY = abs(wY - bY);

    int s = dX + dY;

    if(s % 2 == 0)
        printf("black\n");
    else
        printf("white\n");


    return 0;
}