Added day9

day6/example.txt

@@ -0,0 +1,10 @@
+....#.....
+.........#
+..........
+..#.......
+.......#..
+..........
+.#..^.....
+........#.
+#.........
+......#...

day6/solution.py

@@ -0,0 +1,75 @@
+def count_guard_positions(map_lines):
+    # Convert the map to a mutable 2D list of characters
+    grid = [list(row) for row in map_lines]
+    rows, cols = len(grid), len(grid[0])
+    
+    # Directions: UP=0, RIGHT=1, DOWN=2, LEFT=3
+    directions = [(-1, 0), (0, 1), (1, 0), (0, -1)]
+    
+    # Find the initial guard position '^'
+    start_pos = None
+    for r in range(rows):
+        for c in range(cols):
+            if grid[r][c] == '^':
+                start_pos = (r, c)
+                grid[r][c] = '.'  # Replace '^' with '.'
+                break
+        if start_pos:
+            break
+    
+    # Initialize guard state
+    current_pos = start_pos
+    current_dir = 0  # Start facing UP
+    visited = {current_pos}
+    steps = 0
+    
+    # Large safety limit to prevent infinite loops in case something goes wrong
+    max_steps = rows * cols * 10
+    
+    while True:
+        steps += 1
+        if steps > max_steps:
+            # If something is wrong, break out to avoid infinite loop
+            print("Exceeded maximum expected steps. Stopping.")
+            break
+        
+        # Calculate the next forward position
+        dr, dc = directions[current_dir]
+        next_r = current_pos[0] + dr
+        next_c = current_pos[1] + dc
+        
+        # Check if moving forward would leave the grid
+        if not (0 <= next_r < rows and 0 <= next_c < cols):
+            # The guard leaves the mapped area here
+            break
+        
+        # Check if the next cell is an obstacle
+        if grid[next_r][next_c] == '#':
+            # Can't move forward, turn right
+            current_dir = (current_dir + 1) % 4
+            continue
+        
+        # The next cell is free, move forward
+        current_pos = (next_r, next_c)
+        visited.add(current_pos)
+        # Continue forward in the same direction on the next iteration
+    
+    return len(visited)
+
+
+# Given example grid
+example_grid = [
+    "....#.....",
+    ".........#",
+    "..........",
+    "..#.......",
+    ".......#..",
+    "..........",
+    ".#.^......",
+    "........#.",
+    "#.........",
+    "......#..."
+]
+
+result = count_guard_positions(example_grid)
+print("Result:", result)