2024 Day 12 Part 1 Completed

2024/12/daily.py

@@ -0,0 +1,83 @@
+import itertools
+import sys
+
+def parse(input_text):
+  out = []
+  for line in input_text.strip().split('\n'):
+    if len(line) == 0:
+      continue
+    out.append(list(line))
+
+  return out
+
+CARDINALS = [(0, 1), (0, -1), (1, 0), (-1, 0)]
+
+def blocks(grid, x, y):
+  block = set()
+  block.add((x, y))
+  char = grid[y][x]
+
+  candidates = [(x, y)]
+  while len(candidates) > 0:
+    x, y = candidates.pop()
+    for dx, dy in CARDINALS:
+      new_x = x + dx
+      new_y = y + dy
+      if new_x < 0 or new_x >= len(grid[0]) or new_y < 0 or new_y >= len(grid):
+        continue
+      if (new_x, new_y) in block:
+        continue
+      if grid[new_y][new_x] == char:
+        block.add((new_x, new_y))
+        candidates.append((new_x, new_y))
+
+  return block
+
+def perimeter(grid, block):
+  sum = 0
+  for x, y in block:
+    for dx, dy in CARDINALS:
+      new_x = x + dx
+      new_y = y + dy
+      # Grid Border
+      if new_x < 0 or new_x >= len(grid[0]) or new_y < 0 or new_y >= len(grid):
+        sum += 1
+        continue
+      # Contiguous
+      if (new_x, new_y) in block:
+        continue
+
+      # Borders other blocks on this side
+      sum += 1
+
+  return sum
+
+def part1(input_text):
+  grid = parse(input_text)
+  block_sets = []
+  visited = set()
+
+  for y in range(len(grid)):
+    for x in range(len(grid[y])):
+      if (x, y) in visited:
+        continue
+      block = blocks(grid, x, y)
+      block_sets.append(block)
+      visited.update(block)
+
+  sum = 0
+  for block in block_sets:
+    p = perimeter(grid, block)
+    sum += p * len(block)
+
+  return sum
+
+def part2(input_text):
+  return 0
+
+if __name__ == "__main__":
+  with open(__file__.rsplit('/', 1)[0] + "/input.txt", 'r') as file:
+    print(part1(file.read()))
+
+  with open(__file__.rsplit('/', 1)[0] + "/input.txt", 'r') as file:
+    print(part2(file.read()))

2024/12/daily_test.py

@@ -0,0 +1,45 @@
+import pytest
+from daily import *
+
+@pytest.fixture
+def sample_data():
+  return """
+RRRRIICCFF
+RRRRIICCCF
+VVRRRCCFFF
+VVRCCCJFFF
+VVVVCJJCFE
+VVIVCCJJEE
+VVIIICJJEE
+MIIIIIJJEE
+MIIISIJEEE
+MMMISSJEEE
+"""
+
+@pytest.fixture
+def parsed_data(sample_data):
+  return parse(sample_data)
+
+def test_parse(sample_data):
+  grid = parse(sample_data)
+  assert grid[0][0] == 'R'
+  assert grid[9][9] == 'E'
+
+def test_blocks(parsed_data):
+  pos_set = blocks(parsed_data, 0, 0)
+
+  assert len(pos_set) == 12
+  assert (0,0) in pos_set
+  assert (4,2) in pos_set
+  assert (2,3) in pos_set
+
+def test_perimeter(parsed_data):
+  b = blocks(parsed_data, 0, 0)
+  assert perimeter(parsed_data, b) == 18
+
+
+def test_part1(sample_data):
+  assert part1(sample_data) == 1930
+
+# def test_part2(sample_data):
+#   assert part2(sample_data) == 81