#include <stdio.h>




int main(){
	int w1,w2,b1,b2;
	
	scanf("%d %d\n%d %d", &w1, &w2, &b1, &b2 );
	
	if(((w1%2) + (w2%2))%2 ==(b1%2 + b2%2)%2){
		printf("black\n");
	}
	else{
		printf("white\n");
	}


	return 0;
}