def checkRolls(x: int, y: int) :
	rolls = 0
	#!Check row above
	if y > 0 :
		#Check above left
		if x > 0 and inputGrid[y - 1][x - 1] == "@" :
			rolls += 1
		#Check directly above
		if inputGrid[y - 1][x] == "@" :
			rolls += 1
		#Check above right
		if x < len(inputGrid[y - 1]) - 1 and inputGrid[y - 1][x + 1] == "@" :
			rolls += 1
	#!Check same row
	#Check left
	if x > 0 and inputGrid[y][x - 1] == "@" :
		rolls += 1
	#Check right
	if x < len(inputGrid[y]) - 1 and inputGrid[y][x + 1] == "@":
		rolls += 1
	#!Check row below
	if y < len(inputGrid) - 1 :
		#Check below left
		if x > 0 and inputGrid[y + 1][x - 1] == "@" :
			rolls += 1
		#Check directly below
		if inputGrid[y + 1][x] == "@" :
			rolls += 1
		#Check below right
		if x < len(inputGrid[y]) - 1 and inputGrid[y + 1][x + 1] == "@" :
			rolls += 1
	return rolls


testInput = [
	"..@@.@@@@.",
	"@@@.@.@.@@",
	"@@@@@.@.@@",
	"@.@@@@..@.",
	"@@.@@@@.@@",
	".@@@@@@@.@",
	".@.@.@.@@@",
	"@.@@@.@@@@",
	".@@@@@@@@.",
	"@.@.@@@.@."
]

def readFile() :
	ary = []
	with open("files/Problem4.txt", "r") as file :
		for line in file :
			ary.append(line.replace("\n", ""))
	return ary

def printGrid() :
	for line in inputGrid :
		print(line)
	print("")

def clearGrid() :
	for y in range(len(inputGrid)) :
		newLine = inputGrid[y]
		newLine = newLine.replace("x", ".")
		inputGrid[y] = newLine


#inputGrid = testInput
inputGrid = readFile()
removableRoles = 0
x = 0
y = 0
rollLocations = []
#If accessible roles are found, remove them from the grid and begin again until no more are found
while True :
	#printGrid()
	#clearGrid()
	for y in range(len(inputGrid)) :
		for x in range(len(inputGrid[y])) :
			if inputGrid[y][x] == "@" :
				rollsAround = checkRolls(x, y)
				#print(f"roll at ({x}, {y}) with {rollsAround} rolls around")
				if rollsAround < 4 :
					removableRoles += 1
					#Save X,Y of accessible rolls
					rollLocations.append((x, y))
					#print(f"Accessible roll at ({x}, {y}) with {rollsAround} rolls around")
	if len(rollLocations) == 0 :
		break
	for loc in rollLocations :
		inputGrid[loc[1]] = inputGrid[loc[1]][:loc[0]] + "x" + inputGrid[loc[1]][loc[0] + 1:]
	rollLocations = []
#printGrid()
print(f"Total removable roles = {removableRoles}")

#Too low = 8316