numbers = []

f = open('011.txt', 'r')
for line in f:
	line.rstrip('\n')
	line_str = line.split(' ')
	line_int = [ int(x) for x in line_str ]
	numbers.append(line_int)
f.close()


def find_down():
	max = 0
	for i in range(0, 17):
		for j in range(0, 20):
			product = numbers[i][j] * numbers[i+1][j] * numbers[i+2][j] * numbers[i+3][j]
			if product > max:
				max = product
	return max

def find_right():
	max = 0
	for i in range(0, 20):
		for j in range(0, 17):
			product = numbers[i][j] * numbers[i][j+1] * numbers[i][j+2] * numbers[i][j+3]
			if product > max:
				max = product
	return max

def find_diagonal1():
	max = 0
	for i in range(0, 17):
		for j in range(0, 17):
			product = numbers[i][j] * numbers[i+1][j+1] * numbers[i+2][j+2] * numbers[i+3][j+3]
			if product > max:
				max = product
	return max

def find_diagonal2():
	max = 0
	for i in range(0, 17):
		for j in range(0, 17):
			product = numbers[i][19-j] * numbers[i+1][18-j] * numbers[i+2][17-j] * numbers[i+3][16-j]
			if product > max:
				max = product
	return max

print max(find_down(), find_right(), find_diagonal1(), find_diagonal2())