From 8c3b6556a7b005c261e6faaf5b226a7c8d1ff56a Mon Sep 17 00:00:00 2001
From: Gabriel Augendre <gabriel@augendre.info>
Date: Fri, 6 Mar 2020 17:30:19 +0100
Subject: [PATCH] Solve day 8 part 2

---
 2019/day08-image.py | 51 +++++++++++++++++++++++++++++++--------------
 1 file changed, 35 insertions(+), 16 deletions(-)

diff --git a/2019/day08-image.py b/2019/day08-image.py
index f9f52be..5772a2d 100644
--- a/2019/day08-image.py
+++ b/2019/day08-image.py
@@ -1,29 +1,48 @@
-import math
+from typing import List
+
+WIDTH = 25
+HEIGHT = 6
+LAYER_SIZE = WIDTH * HEIGHT
+
+WHITE = "1"
+BLACK = "0"
+TRANSPARENT = "2"
+
+
+def find_pixel(layers: List[str], index: int) -> str:
+    for layer in layers:
+        pixel = layer[index]
+        if pixel in [WHITE, BLACK]:
+            return pixel
+    return TRANSPARENT
+
+
+def display_image(image: str) -> None:
+    for i, pixel in enumerate(image):
+        if i % WIDTH == 0:
+            print()
+        character = " "
+        if pixel == WHITE:
+            character = "█"
+        print(character, end="")
 
 
 def main():
-    width = 25
-    height = 6
     with open("inputs/day08") as f:
         data = f.readline().strip()
     layers = []
-    layer_size = width * height
     position = 0
-    layer = data[position : position + layer_size]
-    number_of_zero_digits = math.inf
-    layer_index = -1
+    layer = data[position : position + LAYER_SIZE]
     while layer:
-        count = layer.count("0")
-        if count < number_of_zero_digits:
-            layer_index = int(position / layer_size)
-            number_of_zero_digits = count
         layers.append(layer)
-        position += layer_size
-        layer = data[position : position + layer_size]
+        position += LAYER_SIZE
+        layer = data[position : position + LAYER_SIZE]
 
-    print(layer_index)
-    layer = layers[layer_index]
-    print(layer.count("1") * layer.count("2"))
+    result_image = ""
+    for index in range(LAYER_SIZE):
+        result_image += find_pixel(layers, index)
+
+    display_image(result_image)
 
 
 if __name__ == "__main__":