1 files changed, 33 insertions, 0 deletions
diff --git a/12.py b/12.py
new file mode 100644
index 0000000..ae018b7
--- /dev/null
+++ b/12.py
@@ -0,0 +1,33 @@
+from utils import open_day, Point2D, a_star, adjacent_bounded
+
+with open_day(12) as f:
+    inp = []
+    for y, l in enumerate(f):
+        l = l.rstrip()
+        row = []
+        for x, c in enumerate(l):
+            if c == 'S':
+                start = Point2D(x, y)
+                c = 'a'
+            elif c == 'E':
+                end = Point2D(x, y)
+                c = 'z'
+            row.append(ord(c) - ord('a'))
+        inp.append(row)
+
+def h(p): return 0
+def d(a, b): return 1
+def neighbours1(p):
+    height = inp[p.y][p.x]
+    for a in adjacent_bounded(p, Point2D(len(inp[0]), len(inp)), False):
+        adjheight = inp[a.y][a.x]
+        if adjheight - height <= 1: yield a
+
+print(a_star(start, end, neighbours1, h, d))
+def neighbours2(p):
+    height = inp[p.y][p.x]
+    for a in adjacent_bounded(p, Point2D(len(inp[0]), len(inp)), False):
+        adjheight = inp[a.y][a.x]
+        if adjheight - height >= -1: yield a
+def goal(p): return inp[p.y][p.x] == 0
+print(a_star(end, goal, neighbours2, h, d))