[Python/2017] Move solutions into .py files

Python/2017/21.py

@@ -0,0 +1,86 @@
+from lib import *
+
+input = read_input(2017, 21)
+
+lines = input.splitlines()
+
+
+def rotate(p):
+    return tuple("".join(p[j][i] for j in range(len(p))) for i in reversed(range(len(p[0]))))
+
+
+rules = {}
+pattern = ".#.", "..#", "###"
+for line in lines:
+    a, b = [tuple(k.split("/")) for k in line.split(" => ")]
+    rules[a] = b
+
+
+def find_rule(p):
+    for _ in range(4):
+        if p in rules:
+            return rules[p]
+        p = rotate(p)
+
+    p = tuple(reversed(p))
+    for _ in range(4):
+        if p in rules:
+            return rules[p]
+        p = rotate(p)
+
+
+def apply():
+    k = 3 if len(pattern) % 2 else 2
+    out = []
+    for i in range(len(pattern) // k):
+        b = []
+        for j in range(len(pattern) // k):
+            new = find_rule(tuple("".join(pattern[i * k + y][j * k + x] for x in range(k)) for y in range(k)))
+            b.append(new)
+        for line in zip(*b):
+            out.append("".join(line))
+    return tuple(out)
+
+
+for _ in range(5):
+    pattern = apply()
+
+print(sum(line.count("#") for line in pattern))
+
+
+rules = {}
+pattern = ".#.", "..#", "###"
+for line in lines:
+    a, b = [tuple(k.split("/")) for k in line.split(" => ")]
+    rules[a] = b
+
+
+def find_rule(p):
+    for _ in range(4):
+        if p in rules:
+            return rules[p]
+        p = rotate(p)
+    p = tuple(reversed(p))
+    for _ in range(4):
+        if p in rules:
+            return rules[p]
+        p = rotate(p)
+
+
+def apply():
+    k = 3 if len(pattern) % 2 else 2
+    out = []
+    for i in range(len(pattern) // k):
+        b = []
+        for j in range(len(pattern) // k):
+            new = find_rule(tuple("".join(pattern[i * k + y][j * k + x] for x in range(k)) for y in range(k)))
+            b.append(new)
+        for line in zip(*b):
+            out.append("".join(line))
+    return tuple(out)
+
+
+for _ in range(18):
+    pattern = apply()
+
+print(sum(line.count("#") for line in pattern))