day07

2025-12-07 22:23:14 +01:00
parent 376db235e3
commit 7ddc5ac2d8
2 changed files with 241 additions and 0 deletions
@@ -0,0 +1,99 @@
+"""Day X: Advent of Code 2025."""
+
+import time
+from collections import defaultdict
+from aoc import read_lines, read_input, read_grid, read_ints
+import numpy as np
+from functools import lru_cache
+
+
+
+def traverse(start_pos: tuple[int, int], data: np.ndarray, visited: set, collisions: set):
+    start_row, start_col = start_pos
+    if (start_row, start_col) in visited:
+        return
+    
+    visited.add((start_row, start_col))
+    row, col = data.shape
+    r = start_row +  1
+    while True:
+        if r >= row:
+            break
+        v = data[r, start_col]
+        if (r, start_col) in collisions:
+            break
+        if  v == '^':
+            collisions.add((r, start_col))
+            if start_col + 1 < col:
+                traverse((r, start_col + 1), data, visited, collisions)
+            if start_col - 1 >= 0:
+                traverse((r, start_col - 1), data, visited, collisions)
+            break
+        
+        r += 1
+            
+    return
+
+def traverse_2(start_pos: tuple[int, int], data: np.ndarray, cache=None):
+    if cache is None:
+        cache = {}
+    if start_pos in cache:
+        return cache[start_pos]
+
+    start_row, start_col = start_pos
+    row, col = data.shape
+    r = start_row + 1
+    counter = 0
+
+    while True:
+        if r >= row:
+            cache[start_pos] = counter + 1
+            return counter + 1
+        v = data[r, start_col]
+
+        if v == '^':
+            if start_col + 1 < col:
+                counter += traverse_2((r, start_col + 1), data, cache)
+            if start_col - 1 >= 0:
+                counter += traverse_2((r, start_col - 1), data, cache)
+            break
+
+        r += 1
+
+    cache[start_pos] = counter
+    return counter
+        
+def part1(data: np.ndarray):
+    rows, cols = np.where(data == 'S')
+    if len(rows) == 0:
+        raise ValueError("Start 'S' not found in grid")
+    start_row, start_col = int(rows[0]), int(cols[0])
+    collision = set()
+    visited = set()
+    traverse((start_row, start_col), data, visited, collision)
+    print(data)
+    return len(collision)
+
+
+def part2(data):
+    rows, cols = np.where(data == 'S')
+    if len(rows) == 0:
+        raise ValueError("Start 'S' not found in grid")
+    start_row, start_col = int(rows[0]), int(cols[0])
+    counter = traverse_2((start_row, start_col), data)
+    return counter
+
+
+if __name__ == "__main__":
+    DAY = 7  # <- ändra till rätt dag
+    data = read_grid(DAY)
+
+    t0 = time.perf_counter()
+    p1 = part1(data)
+    t1 = time.perf_counter()
+    print(f"Part 1: {p1}  ({(t1-t0)*1000:.2f} ms)")
+
+    t0 = time.perf_counter()
+    p2 = part2(data)
+    t1 = time.perf_counter()
+    print(f"Part 2: {p2}  ({(t1-t0)*1000:.2f} ms)")