day 6 done. im sure part 2 could be done better

2024/06/part 1 solution.py

@@ -0,0 +1,66 @@
+testing = 0
+if not testing:
+    with open(r"2024/06\input.txt", "r") as file:
+        input = file.read()
+else:
+    input = """....#.....
+.........#
+..........
+..#.......
+.......#..
+..........
+.#..^.....
+........#.
+#.........
+......#..."""
+
+OBSTACLE = "#"
+# first we should turn the input into a list of lists so we can use grid references
+
+input = input.split("\n")
+grid = [list(x) for x in input]
+
+# for x in grid:
+#     print(x)
+
+# we need to find the starting position
+# our starting position is the only '^' in the grid
+for x in range(len(grid)):
+    for y in range(len(grid[x])):
+        if grid[x][y] == "^":
+            position = (x, y)
+            break
+print('start at',position)
+
+# We start by travelling north until we hit an obstacle '#'
+# then we turn right and travel east until we hit an obstacle
+# we keep turning right and travelling until we hit an obstacle
+# once we make it off the grid we stop
+# count how many unique squares we visit
+
+def count_unique_squares(grid, start):
+    directions = [(-1, 0), (0, 1), (1, 0), (0, -1)]  # North, East, South, West
+    direction_index = 0  # Start by moving north
+    x, y = start
+    visited = set()
+
+    while True:
+        visited.add((x, y))
+        dx, dy = directions[direction_index]
+        new_x, new_y = x + dx, y + dy
+        # if new position is off the grid, we stop
+        if (new_x < 0 or new_x >= len(grid) or new_y < 0 or new_y >= len(grid[0])):
+            print(f"Moved off the grid to ({new_x}, {new_y}), stopping")
+            break
+        # if we hit an obstacle, we turn right
+        elif grid[new_x][new_y] == OBSTACLE:
+            direction_index = (direction_index + 1) % 4  # Turn right
+            print(f"Hit obstacle at ({new_x}, {new_y}), turning right to direction {directions[direction_index]}")
+        
+        else:
+            x, y = new_x, new_y
+            print(f"Moved to ({x}, {y})")
+
+    return len(visited)
+
+print(count_unique_squares(grid, position))

2024/06/part 2 solution.py

@@ -0,0 +1,74 @@
+testing = 0
+if not testing:
+    with open(r"2024/06\input.txt", "r") as file:
+        input = file.read()
+else:
+    input = """....#.....
+.........#
+..........
+..#.......
+.......#..
+..........
+.#..^.....
+........#.
+#.........
+......#..."""
+
+OBSTACLE = "#"
+# first we should turn the input into a list of lists so we can use grid references
+
+split_input = input.split("\n")
+grid = [list(x) for x in split_input]
+ROWS = len(grid)
+COLUMNS = len(grid[0])
+
+# for x in grid:
+#     print(x)
+
+# we need to find the starting position
+# our starting position is the only '^' in the grid
+for x in range(len(grid)):
+    for y in range(len(grid[x])):
+        if grid[x][y] == "^":
+            position = (x, y)
+            break
+#print('start at',position)
+
+# We start by travelling north until we hit an obstacle '#'
+# then we turn right and travel east until we hit an obstacle
+# we keep turning right and travelling until we hit an obstacle
+# once we make it off the grid we stop
+# count how many unique squares we visit
+
+loops = 0
+for row in range(ROWS):
+    for col in range(COLUMNS):
+        directions = [(-1, 0), (0, 1), (1, 0), (0, -1)]  # North, East, South, West
+        direction_index = 0  # Start by moving north
+        x, y = position
+        visited = set()
+        visited_with_direction = set() # used for loop detection
+        while True:
+            visited.add((x, y))
+            if (x, y, direction_index) in visited_with_direction:
+                #print(f"Loop detected at ({x}, {y}) in direction {directions[direction_index]}")
+                loops += 1
+                break
+            visited_with_direction.add((x, y, direction_index))
+            dx, dy = directions[direction_index]
+            new_x, new_y = x + dx, y + dy
+            # if new position is off the grid, we stop
+            if (new_x < 0 or new_x >= len(grid) or new_y < 0 or new_y >= len(grid[0])):
+                #print(f"Moved off the grid to ({new_x}, {new_y}), stopping")
+                break
+            # if we hit an obstacle, we turn right
+            elif (grid[new_x][new_y] == OBSTACLE or (new_x, new_y) == (row,col)):
+                direction_index = (direction_index + 1) % 4  # Turn right
+                #print(f"Hit obstacle at ({new_x}, {new_y}), turning right to direction {directions[direction_index]}")
+            
+            else:
+                x, y = new_x, new_y
+                #print(f"Moved to ({x}, {y})")
+
+print('part 1 answer',len(visited))
+print('part 2 answer',loops)

get_puzzle_text.py

@@ -90,8 +90,13 @@ def create_solution_file(year, day, part):
     # Check if the solution file already exists
     if not os.path.exists(solution_file):
         with open(solution_file, "w") as file:
-            file.write(f"""with open(r'{input_file_path}', 'r') as file:
+            file.write(f"""testing = 1
+if not testing:
+    with open(r"{year}/{day:02}\input.txt", "r") as file:
         input = file.read()
+else:
+    input = '''
+'''
 """)
         print(f"Created {solution_file}")
     else: