started 2025 day5 parts 1 & 2

2025/day4/part1/main.py

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+INPUT_FILE = "input.txt"
+
+# True for roll of paper
+floor: list[list[bool]] = [ [ c == '@' for c in line.strip() ] for line in open(INPUT_FILE, 'r').readlines() ]
+
+class iVec2d:
+    x: int
+    y: int
+
+    def __init__(self, x: int, y: int):
+        self.x = x
+        self.y = y
+
+max_y = len(floor)
+max_x = len(floor[0])
+
+min_y = 0
+min_x = 0
+
+def count_neighbors(floor: list[list[bool]], pos: iVec2d) -> int:
+    DIRECTIONS = [
+        iVec2d(-1, -1),
+        iVec2d(0, -1),
+        iVec2d(1, -1),
+        iVec2d(-1, 0),
+        iVec2d(1, 0),
+        iVec2d(-1, 1),
+        iVec2d(0, 1),
+        iVec2d(1, 1)
+    ]
+
+    neighbors = 0
+    for direction in DIRECTIONS:
+        dx, dy = direction.x, direction.y
+
+        new_x = pos.x + dx
+        new_y = pos.y + dy
+
+        if new_x >= max_x or new_x < min_x:
+            continue
+
+        if new_y >= max_y or new_y < min_y:
+            continue
+
+        if floor[new_y][new_x]:
+            neighbors += 1
+
+    return neighbors
+
+moveable_rolls = 0
+for y in range(len(floor)):
+    for x in range(len(floor[0])):
+
+        pos = iVec2d(x, y)
+
+        if floor[pos.y][pos.x]:
+            if count_neighbors(floor, pos) < 4:
+                moveable_rolls += 1
+                print('x', end='')
+            else:
+                print('@', end='')
+        else:
+            print('.', end='')
+
+    print()
+
+print(f'Moveable Rolls: {moveable_rolls}')
+
+