#!/usr/bin/env python3

ZERO, ONE, TWO = "012"

BLACK = 0
WHITE = 1

color = {WHITE : u"\u2B1C",
         BLACK : u"\u2B1B"
        }


class Image:
    def __init__(self, data, w, h):
        self.data = data
        self.w    = w
        self.h    = h

    def layers(self):
        w, h = self.w, self.h
        return (self.data[i:i+w*h] for i in range(0, len(self.data), w*h))

    def image(self):
        final = str()
        for stack in zip(*self.layers()):
            final += (''.join(stack).replace(TWO, "") + TWO)[0]
        return final

    def __repr__(self):
        w, image = self.w, self.image()
        return '\n'.join(image[i:i+w] for i in range(0, len(image), w))

    def __str__(self):
        return repr(self).replace(ZERO, color[BLACK]).replace(ONE, color[WHITE])



def preproc(puzzle_input):
    w, h = 25, 6
    data = puzzle_input.replace('\n', '')
    return Image(data, w, h)

def partI(image):
    layer = min(image.layers(), key=lambda ly: ly.count(ZERO))
    return layer.count(ONE) * layer.count(TWO)

def partII(image):
    return '\n' + str(image)