Day 18: prepare cool grid

2019/day18.py

@@ -0,0 +1,20 @@
+from grid import Grid
+
+
+def main():
+    with open("day18.txt", "rt") as input_file:
+        lines = input_file.readlines()
+    
+    lab = Lab(lines)
+    lab.dumb_print()
+
+
+class Lab(Grid):
+
+    TILE_PATH = "."
+    TILE_WALL = "#"
+    TILE_START = "@"
+
+
+if __name__ == "__main__":
+    main()

2019/grid.py

@@ -1,25 +1,36 @@
+"""Generic 2D grid with a few helpers."""
+
 from collections import defaultdict
 
 
 class Grid:
 
-    def __init__(self):
+    def __init__(self, lines=None):
         self.g = defaultdict(lambda: defaultdict(int))
+        if lines:
+            self.load(lines)
 
-    @staticmethod
-    def near(p):
-        """Return a tuple of neighbor positions (up, left, down, right)."""
-        return (
-            (p[0]    , p[1] - 1),
-            (p[0] + 1, p[1]    ),
-            (p[0]    , p[1] + 1),
-            (p[0] - 1, p[1]    ),
-        )
+    def load(self, lines, f=lambda v: v):
+        for y, line in enumerate(lines):
+            for x, c in enumerate(line.rstrip()):
+                self.g[y][x] = f(c)
+
+    def getv(self, x, y):
+        return self.g[y][x]
+    
+    def setv(self, x, y, value):
+        self.g[y][x] = value
 
     def near_items(self, p):
         """Return a dict of neighbor positions to values (U, L, D, R)."""
         return {pos: self.g[pos[1]][pos[0]] for pos in Grid.near(p)}
 
+    def dumb_print(self, f=lambda v: v):
+        for row in self.g.values():
+            for x in row.values():
+                print(f(x), end="")
+            print()
+
     def print_near(self, p):
         print("".join([
             chr(self.g[p[1] - 1][p[0] - 1]),
@@ -36,3 +47,13 @@ class Grid:
             chr(self.g[p[1] + 1][p[0]]),
             chr(self.g[p[1] + 1][p[0] + 1]),
         ]))
+
+    @staticmethod
+    def near(p):
+        """Return a tuple of neighbor positions (up, left, down, right)."""
+        return (
+            (p[0]    , p[1] - 1),
+            (p[0] + 1, p[1]    ),
+            (p[0]    , p[1] + 1),
+            (p[0] - 1, p[1]    ),
+        )