package main

import "fmt"

var grid [20*20]int

func i(x, y int) int {
	return grid[(20 * y) + x]
}

func main(){
	grid = [20*20]int {
		8,2,22,97,38,15,0,40,0,75,04,05,07,78,52,12,50,77,91,8,
		49,49,99,40,17,81,18,57,60,87,17,40,98,43,69,48,04,56,62,00,
		81,49,31,73,55,79,14,29,93,71,40,67,53,88,30,03,49,13,36,65,
		52,70,95,23,04,60,11,42,69,24,68,56,01,32,56,71,37,02,36,91,
		22,31,16,71,51,67,63,89,41,92,36,54,22,40,40,28,66,33,13,80,
		24,47,32,60,99,03,45,02,44,75,33,53,78,36,84,20,35,17,12,50,
		32,98,81,28,64,23,67,10,26,38,40,67,59,54,70,66,18,38,64,70,
		67,26,20,68,02,62,12,20,95,63,94,39,63,8,40,91,66,49,94,21,
		24,55,58,05,66,73,99,26,97,17,78,78,96,83,14,88,34,89,63,72,
		21,36,23,9,75,00,76,44,20,45,35,14,00,61,33,97,34,31,33,95,
		78,17,53,28,22,75,31,67,15,94,03,80,04,62,16,14,9,53,56,92,
		16,39,05,42,96,35,31,47,55,58,88,24,00,17,54,24,36,29,85,57,
		86,56,00,48,35,71,89,07,05,44,44,37,44,60,21,58,51,54,17,58,
		19,80,81,68,05,94,47,69,28,73,92,13,86,52,17,77,04,89,55,40,
		04,52,8,83,97,35,99,16,07,97,57,32,16,26,26,79,33,27,98,66,
		88,36,68,87,57,62,20,72,03,46,33,67,46,55,12,32,63,93,53,69,
		04,42,16,73,38,25,39,11,24,94,72,18,8,46,29,32,40,62,76,36,
		20,69,36,41,72,30,23,88,34,62,99,69,82,67,59,85,74,04,36,16,
		20,73,35,29,78,31,90,01,74,31,49,71,48,86,81,16,23,57,05,54,
		01,70,54,71,83,51,54,69,16,92,33,48,61,43,52,01,89,19,67,48 }

	highest := 0

	// Check horizontals
	for x := 0; x < 16; x += 1 {
		for y := 0; y < 20; y += 1 {
			product := i(x,y) * i(x+1,y) * i(x+2, y) * i(x+3, y)
			if product > highest {
				highest = product
			}
		}
	}

	//verticals
	for x := 0; x < 20; x += 1 {
		for y := 0; y < 16; y += 1 {
			product := i(x,y) * i(x,y+1) * i(x, y+2) * i(x, y+3)
			if product > highest {
				highest = product
			}
		}
	}

	//backslash
	for x := 0; x < 16; x += 1 {
		for y := 0; y < 16; y += 1 {
			product := i(x,y) * i(x+1,y+1) * i(x+2, y+2) * i(x+3, y+3)
			if product > highest {
				highest = product
			}
		}
	}

	//forwardslash
	for x := 3; x < 20; x += 1 {
		for y := 0; y < 16; y += 1 {
			product := i(x,y) * i(x-1,y+1) * i(x-2, y+2) * i(x-3, y+3)
			if product > highest {
				highest = product
			}
		}
	}

	fmt.Print(highest, "\n")
}