2024 Day 18 Part 1 Completed

2024/18/daily.py

@@ -0,0 +1,109 @@
+import queue
+
+def parse(input_text):
+  falling_bytes = []
+  falling_bytes_map = {}
+
+  max_x = 0
+  may_y = 0
+  for line in input_text.strip().split('\n'):
+    if len(line) == 0:
+      continue
+
+    x, y = tuple(map(int,line.split(',')))
+    if x > max_x:
+      max_x = x
+    if y > may_y:
+      may_y = y
+
+    # Starts at zeroth-nanosecond
+    falling_bytes_map[(x, y)] = len(falling_bytes)
+    falling_bytes.append((x, y))
+
+  grid = []
+
+  for y in range(may_y + 1):
+    g = []
+    for x in range(max_x + 1):
+      if (x, y) in falling_bytes:
+        # Starts at zeroth-nanosecond
+        g.append(falling_bytes.index((x, y)))
+      else:
+        g.append(None)
+    grid.append(g)
+
+  return falling_bytes_map, grid
+
+def render(grid, time):
+  for y in range(len(grid)):
+    for x in range(len(grid[y])):
+      if grid[y][x] == None:
+        print('.', end='')
+      elif grid[y][x] <= time:
+        print('#', end='')
+      else:
+        print('_', end='')
+    print()
+
+  print()
+
+def distance(a, b):
+  return abs(a[0] - b[0]) + abs(a[1] - b[1])
+
+def pathfinder(fb_map, time_code, s, e):
+  best_steps = 99999999
+
+  candidates = queue.PriorityQueue()
+  candidates.put((distance(s, e)*3, s, 0))
+  visited = {}
+
+  counter = 0
+  while not candidates.empty():
+    counter += 1
+    score, pos, steps = candidates.get()
+
+    if pos in visited:
+      if visited[pos] > steps:
+        visited[pos] = steps
+      else:
+        continue
+    else:
+      visited[pos] = steps
+
+    if pos == e:
+      if steps < best_steps:
+        best_steps = steps
+      continue
+
+    for dx, dy in [(-1, 0), (1, 0), (0, -1), (0, 1)]:
+      nx, ny = pos
+      nx += dx
+      ny += dy
+
+      # blocked by bounds of grid
+      if nx < 0 or nx > e[0] or ny < 0 or ny > e[1]:
+        continue
+      # blocked by falling block
+      if (nx, ny) in fb_map and fb_map[(nx, ny)] < time_code:
+        continue
+
+      # candidates.put((distance((nx, ny), e) + steps, (nx, ny), steps + 1))
+      # print(f"Putting: {nx}, {ny}, {steps + 1}")
+      candidates.put((distance((nx, ny), e)*3 + steps + 1, (nx, ny), steps + 1))
+
+  print(f"Counter: {counter}")
+  return best_steps
+
+def part1(input_text, time_code, s, e):
+    fb_map, _ = parse(input_text)
+    return pathfinder(fb_map, time_code, s, e)
+
+def part2(input_text):
+  return 0
+
+if __name__ == "__main__":
+  with open(__file__.rsplit('/', 1)[0] + "/input.txt", 'r') as file:
+    print(part1(file.read(), 1024, (0, 0), (70, 70)))
+
+  with open(__file__.rsplit('/', 1)[0] + "/input.txt", 'r') as file:
+    print(part2(file.read()))

2024/18/daily_test.py

@@ -0,0 +1,54 @@
+import pytest
+from daily import *
+
+@pytest.fixture
+def sample_data():
+  return """
+5,4
+4,2
+4,5
+3,0
+2,1
+6,3
+2,4
+1,5
+0,6
+3,3
+2,6
+5,1
+1,2
+5,5
+2,5
+6,5
+1,4
+0,4
+6,4
+1,1
+6,1
+1,0
+0,5
+1,6
+2,0
+"""
+
+@pytest.fixture
+def parsed_data(sample_data):
+  return parse(sample_data)
+
+def test_parse(sample_data):
+  fb_map, grid= parse(sample_data)
+
+  assert len(fb_map) == 25
+  assert fb_map[(5,4)] == 0
+  assert fb_map[(2,0)] == 24
+
+def test_pathfinder(parsed_data):
+  fb_map, grid = parsed_data
+  render(grid, 12)
+  assert pathfinder(fb_map, 12, (0,0), (6,6)) == 22
+
+def test_part1(sample_data):
+  assert part1(sample_data, 12, (0,0), (6,6)) == 22
+
+# def test_part2(sample_data):
+#   assert part2(sample_data) == 45