Add solution for day 10 part 1

day10/input.txt

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+#..#.#.#.######..#.#...##
+##.#..#.#..##.#..######.#
+.#.##.#..##..#.#.####.#..
+.#..##.#.#..#.#...#...#.#
+#...###.##.##..##...#..#.
+##..#.#.#.###...#.##..#.#
+###.###.#.##.##....#####.
+.#####.#.#...#..#####..#.
+.#.##...#.#...#####.##...
+######.#..##.#..#.#.#....
+###.##.#######....##.#..#
+.####.##..#.##.#.#.##...#
+##...##.######..##..#.###
+...###...#..#...#.###..#.
+.#####...##..#..#####.###
+.#####..#.#######.###.##.
+#...###.####.##.##.#.##.#
+.#.#.#.#.#.##.#..#.#..###
+##.#.####.###....###..##.
+#..##.#....#..#..#.#..#.#
+##..#..#...#..##..####..#
+....#.....##..#.##.#...##
+.##..#.#..##..##.#..##..#
+.##..#####....#####.#.#.#
+#..#..#..##...#..#.#.#.##

day10/py/main.py

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+import sys
+import fractions
+from typing import Tuple, Set
+
+ASTEROID_CHAR = '#'
+SPACE_CHAR = '.'
+
+
+def get_items_in_slope(space_map: Tuple[Tuple[str]], start_row: int, start_col: int, rise: int, run: int) -> Tuple[Tuple[int, int]]:
+    row = start_row
+    col = start_col
+    items = []
+    while row >= 0 and col >= 0 and row < len(space_map) and col < len(space_map[row]):
+        if row == start_row and col == start_col:
+            row += rise
+            col += run
+            continue
+
+        items.append((row, col))
+        row += rise
+        col += run
+
+    return tuple(items)
+
+
+def search_for_visible_in_all_directions(space_map: Tuple[Tuple[str, ...]], start_row: int, start_col: int, rise: int, run: int) -> Set[Tuple[int, int]]:
+    asteroids = set()
+    for i in (-1, 1):
+        for j in (-1, 1):
+            line_items = get_items_in_slope(space_map, start_row, start_col, i * rise, j * run)
+            for row, col in line_items:
+                if space_map[row][col] == ASTEROID_CHAR:
+                    asteroids.add((row, col))
+                    break
+
+    return asteroids
+
+
+def get_visible_asteroid_count(space_map: Tuple[Tuple[str, ...]], start_row: int, start_col: int) -> int:
+    asteroids = set()
+    # This is so beyond gross, but it handles an edge case for checking both directions of the horizontal and vertical
+    for col in range(start_col-1, -1, -1):
+        if space_map[start_row][col] == ASTEROID_CHAR:
+            asteroids.add((start_row, col))
+            break
+
+    for col in range(start_col+1, len(space_map)):
+        if space_map[start_row][col] == ASTEROID_CHAR:
+            asteroids.add((start_row, col))
+            break
+
+    for row in range(start_row-1, -1, -1):
+        if space_map[row][start_col] == ASTEROID_CHAR:
+            asteroids.add((row, start_col))
+            break
+
+    for row in range(start_row+1, len(space_map[0])):
+        if space_map[row][start_col] == ASTEROID_CHAR:
+            asteroids.add((row, start_col))
+            break
+
+    used_slopes = set()
+    for rise in range(1, len(space_map)):
+        for run in range(1, len(space_map[0])):
+            slope_fraction = fractions.Fraction(rise, run)
+            if slope_fraction in used_slopes:
+                continue
+
+            used_slopes.add(slope_fraction)
+            rise, run = slope_fraction.numerator, slope_fraction.denominator
+            found_asteroids = search_for_visible_in_all_directions(space_map, start_row, start_col, rise, run)
+            asteroids = asteroids.union(found_asteroids)
+
+    return len(asteroids)
+
+
+def part1(space_map: Tuple[Tuple[int]]):
+    best_count = None
+    for i, row in enumerate(space_map):
+        for j, item in enumerate(row):
+            if item != ASTEROID_CHAR:
+                continue
+            visible_asteroid_count = get_visible_asteroid_count(space_map, i, j)
+            if best_count is None or visible_asteroid_count > best_count:
+                best_count = visible_asteroid_count
+
+    return best_count
+
+
+if __name__ == "__main__":
+    if len(sys.argv) != 2:
+        print("Usage: ./main.py in_file")
+        sys.exit(1)
+
+    with open(sys.argv[1]) as f:
+        inputs = tuple(tuple(line.strip()) for line in f.readlines())
+
+    for row in inputs:
+        print(''.join(row))
+
+    print(part1(inputs))

day10/sample1.txt

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+.#..#
+.....
+#####
+....#
+...##

day10/sample2.txt

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+......#.#.
+#..#.#....
+..#######.
+.#.#.###..
+.#..#.....
+..#....#.#
+#..#....#.
+.##.#..###
+##...#..#.
+.#....####