Code based on Manuel Blum's algorithm for memorizing passwords, using the Linotype standard.

blum-algorithm.py

#Blum's algorithm for memorizing passwords.
#Made by Pedro Rodríguez de Oliveira (WolfangAukang), 2015.

#Linotype ordered matrix, with the variant of the numeric digits
linotype = [['e','t','a','o','i','n'],['s','h','r','d','l','u'],['c','m','f','w','y','p'],['v','b','g','k','q','j'],['x','z','0','1','2','3'],['4','5','6','7','8','9']]

#String receptor
def blumcrypto(strToCode):
	strToCode = [x.lower() for x in list(strToCode)]
	print (blumcryptoEncr([x.lower() for x in list(strToCode)])) #We will work with lowercase letters

#Main algorithm, converter
def blumcryptoEncr(listToCode):
	#Direction indicator, which is North(0), East(1), South(2), West(3)
	direction = 0
	for i in range(0,len(listToCode)):
		if listToCode[i] != " ": #Ignore spaces
			positions = returnXY(listToCode[i])
			if positions == -1: #Invalid character has been read, send error
				return("Error, invalid character on input. It must contain characters from A to Z or 0 to 9")
			xpos = positions[0]
			ypos = positions[1]
			if direction == 0: #North
				listToCode[i] = linotype[(ypos-1)%6][xpos].title()
			elif direction == 1: #East
				listToCode[i] = linotype[ypos][(xpos+1)%6].title()
			elif direction == 2: #South
				listToCode[i] = linotype[(ypos+1)%6][xpos].title()
			else: #West
				listToCode[i] = linotype[ypos][(xpos-1)%6].title()
			#Add to direction
			direction = (direction + 1) % 4
	#Return converted string
	return "".join(listToCode)

#Character finder on Linotype matrix
def returnXY(char):
	for y in range(0,len(linotype)):
		for x in range(0,len(linotype)):
			if linotype[y][x] == char: #If found, return positions on list
				return [x,y]
return -1 #If not found, return -1