#include <stdio.h>

int main()
{
int a ,b ,c ,d;
scanf("%d %d %d %d",&a,&b,&c,&d);
if(a >= 1 && a <= 8 && b >= 1 && b <= 8 && c >= 1 && c <= 8 && d >= 1 && d <= 8){
if((a+b)%2 == 0 && (c+d)%d == 0 || (a+b)%2 == 1 && (c+d)%2 == 1)
printf("black\n");
if((a+b)%2 == 0 && (c+d)%2 == 1 || (a+b)%2 == 1 && (c+d)%2 == 0)
printf("white\n");
}
return 0;
}