Solve 2019 day 8

2019/d8.py

@@ -0,0 +1,69 @@
+from lib import get_data, str_to_ints
+
+
+def part_1(data):
+    wide = 25
+    tall = 6
+    xs = [int(c) for c in data.strip()]
+    layers = []
+    i = 0
+    while i < len(xs):
+        if i % (wide * tall) == 0:
+            layers.append([])
+        layers[-1].append(xs[i])
+        i += 1
+
+    min_zero_layer = None
+    min_zeros = 10**9
+    for layer in layers:
+        zeros = layer.count(0)
+        if zeros < min_zeros:
+            min_zeros = zeros
+            min_zero_layer = layer
+    ones = min_zero_layer.count(1)
+    twos = min_zero_layer.count(2)
+    print(ones * twos)
+
+
+def part_2(data):
+    wide = 25
+    tall = 6
+    xs = [int(c) for c in data.strip()]
+    layers = []
+    i = 0
+    while i < len(xs):
+        if i % (wide * tall) == 0:
+            layers.append([])
+        layers[-1].append(xs[i])
+        i += 1
+    result = []
+    for i in range(wide * tall):
+        current = 2
+        for layer in layers:
+            pixel = layer[i]
+            if current == 2:
+                current = pixel
+        result.append(current)
+
+    for row in range(tall):
+        row_str = ""
+        for col in range(wide):
+            pixel_idx = row * wide + col
+            pixel = result[pixel_idx]
+            if pixel == 0:
+                row_str += "⬛"
+            elif pixel == 1:
+                row_str += "⬜"
+            else:
+                assert False
+        print(row_str)
+
+
+def main():
+    data = get_data(__file__)
+    part_1(data)
+    part_2(data)
+
+
+if __name__ == "__main__":
+    main()