day8

8/8.py

@@ -0,0 +1,82 @@
+#!/usr/bin/env python3
+
+import sys, os
+
+if len(sys.argv) < 3:
+    print(sys.argv[0], "width", "height")
+    exit()
+
+width = int(sys.argv[1])
+height = int(sys.argv[2])
+
+for line in sys.stdin:
+    pixels = line.rstrip()
+
+    layer = 0
+    x = 0
+    y = 0
+    layers = []
+    counts = []
+
+    row = []
+    layer = []
+
+    zeroes = 0
+    ones = 0
+    twos = 0
+
+    # build layers.
+    for i in range(0, len(pixels)):
+        pixel = int(pixels[i])
+
+        if pixel == 0:
+            zeroes += 1
+        elif pixel == 1:
+            ones += 1
+        elif pixel == 2:
+            twos += 1
+
+        row.append(pixel)
+        x += 1
+
+        # Assemble layer
+        if x == width:
+            x = 0
+            y += 1
+            layer.append(row)
+            row = []
+            
+        # Add layer, stats and reset counts
+        if y == height:
+            y = 0
+            layers.append(layer)
+            counts.append((zeroes, ones, twos))
+            layer = []
+            zeroes = 0
+            ones = 0
+            twos = 0
+
+    # return part 1 answer
+    fewest = None
+    wanted = 0
+    for layer in counts:
+        if fewest is None or layer[0] < fewest:
+            wanted = layer[1] * layer[2]
+            fewest = layer[0]   
+    print(wanted)
+
+    # render part 2 answer
+    for y in range(0,height):
+        row = ""
+        for x in range(0, width):
+            p = 2
+            for l in range(0, len(layers)): 
+                if p == 2:
+                    p = layers[l][y][x]
+            if p == 0:
+                row = row + " " 
+            else:
+                row = row + "*"
+        print(row)
+            
+