white = [int(x) for x in input().split(' ')]
black = [int(x) for x in input().split(' ')]

# True if even
def even():
	if white == black or ((abs(white[0] - black[0]) == 1) and (abs(white[1] - black[1]) == 1)):
		return True
	else: return False
		
so_far_even = True
while abs(white[0] - black[0]) > 1 or abs(white[1] - black[1]) > 1:
		
	so_far_even = not so_far_even
	vec1 = black[0] - white[0]
	vec2 = black[1] - white[1]
	if vec1 == 0: vec1 = 1
	if vec2 == 0: vec2 = 1
	if abs(vec1) > abs(vec2):
		
		vec2 = vec2/(abs(vec2))
		vec1 = 2*(vec1/(abs(vec1)))
		
	else: 
		vec2 = 2*(vec2/(abs(vec2)))
		vec1 = vec1/(abs(vec1))
	white[0] += vec1
	white[1] += vec2
	
if (so_far_even and even()) or ((not (so_far_even)) and (not even())): print("black")
else: print ("white")