day24

1 files changed, 125 insertions, 0 deletions

diff --git a/2022/day24.py b/2022/day24.py
new file mode 100755
index 0000000..ac72b58
--- /dev/null
+++ b/2022/day24.py
@@ -0,0 +1,125 @@
+#!/usr/bin/env python3
+
+# import numpy as np
+from functools import reduce
+from re import findall
+from copy import deepcopy
+from collections import defaultdict
+import sys
+
+# filename = "in/day24.ref"
+filename = "in/day24.pzl"
+data = open(filename).read()
+lines = [line for line in data.rstrip('\n').split('\n')]
+# print(lines)
+
+D = dict()
+for y,line in enumerate(lines):
+    for x,val in enumerate(line):
+        if val != '.':
+            D[(y,x)] = val
+
+def get_max(D):
+    min_y = 1000
+    max_y = 0
+    min_x = 1000
+    max_x = 0
+    for y,x in D:
+        min_y = min(min_y, y)
+        max_y = max(max_y, y)
+        min_x = min(min_x, x)
+        max_x = max(max_x, x)
+    return min_y, max_y, min_x, max_x
+
+def print_grid(D, P):
+    min_y, max_y, min_x, max_x = get_max(D)
+    for y in range(min_y, max_y + 1):
+        for x in range(min_x, max_x + 1):
+            if (y,x) in P:
+                print('E',end='')
+            elif (y,x) in D:
+                print(D[(y,x)][0],end='')
+            else:
+                print('.', end='')
+        print()
+    print()
+    print()
+
+min_y, max_y, min_x, max_x = get_max(D)
+
+start_x = 1
+end_x = max_x - 1
+
+def get_next_D(D):
+    Dn = defaultdict(list)
+    for (y,x) in D:
+        for val in D[(y,x)]:
+            if val == '#':
+                Dn[(y,x)].append('#')
+
+            elif val == '>':
+                nx = x + 1
+                if nx == max_x:
+                    nx = 1
+                Dn[(y,nx)].append('>')
+
+            elif val == '<':
+                nx = x - 1
+                if nx == 0:
+                    nx = max_x - 1
+                Dn[(y,nx)].append('<')
+
+            elif val == 'v':
+                ny = y + 1
+                if ny == max_y:
+                    ny = 1
+                Dn[(ny,x)].append('v')
+
+            elif val == '^':
+                ny = y - 1
+                if ny == 0:
+                    ny = max_y - 1
+                Dn[(ny,x)].append('^')
+    return Dn
+
+def dfs(Dstart, Pstart, Pend):
+    P = Pstart
+    D = Dstart
+
+    it = 0
+    for _ in range(1000):
+        it += 1
+        Pn = set()
+
+        D = get_next_D(D)
+
+        for y,x in P:
+            for dy,dx in [0,0], [1,0], [-1,0], [0,1], [0,-1]:
+                if 0 <= y+dy <= max_y and 0 <= x+dx <= max_x:
+                    if (y+dy, x+dx) not in D:
+                        Pn.add((y+dy,x+dx))
+        P = Pn
+
+        # print_grid(D, P)
+        # print(P)
+
+        for (y,x) in P:
+            if (y,x) in Pend:
+                return D, it
+
+
+Pstart = set()
+Pstart.add((0,1))
+Pend = set()
+Pend.add((max_y, max_x-1))
+
+D, t1 = dfs(D, Pstart, Pend)
+D, t2 = dfs(D, Pend, Pstart)
+D, t3 = dfs(D, Pstart, Pend)
+
+res1 = t1
+res2 = t1 + t2 + t3
+
+print('res1:', res1)
+print('res2:', res2)
+