[Python/2019] Restructure solutions

Python/2019/12.py

@@ -0,0 +1,57 @@
+from lib import *
+
+input = read_input(2019, 12)
+
+moons = []
+for line in input.splitlines():
+    x, y, z = map(int, re.match(r"^<x=([\-\d]+), y=([\-\d]+), z=([\-\d]+)>$", line).groups())
+    moons.append(([x, y, z], [0, 0, 0]))
+
+for _ in range(1000):
+    for pos, vel in moons:
+        for p2, _ in moons:
+            for i in range(3):
+                if pos[i] < p2[i]:
+                    vel[i] += 1
+                elif pos[i] > p2[i]:
+                    vel[i] -= 1
+    for pos, vel in moons:
+        for i in range(3):
+            pos[i] += vel[i]
+print(sum(sum(map(abs, pos)) * sum(map(abs, vel)) for pos, vel in moons))
+
+
+moons = []
+for line in input.splitlines():
+    x, y, z = map(int, re.match(r"^<x=([\-\d]+), y=([\-\d]+), z=([\-\d]+)>$", line).groups())
+    moons.append(([x, y, z], [0, 0, 0]))
+
+
+def make_state(dim):
+    return tuple(e[dim] for moon in moons for e in moon)
+
+
+def simulate_dimension(dim):
+    history = {}
+    time = 0
+    while True:
+        state = make_state(dim)
+        if state in history:
+            return time - history[state]
+        history[state] = time
+        time += 1
+
+        for pos, vel in moons:
+            for p2, _ in moons:
+                if pos[dim] < p2[dim]:
+                    vel[dim] += 1
+                elif pos[dim] > p2[dim]:
+                    vel[dim] -= 1
+        for pos, vel in moons:
+            pos[dim] += vel[dim]
+
+
+x, y, z = map(simulate_dimension, range(3))
+out = x * y // math.gcd(x, y)
+out = out * z // math.gcd(out, z)
+print(out)