48 lines
1.2 KiB
Python
48 lines
1.2 KiB
Python
|
import math
|
||
|
|
|
||
|
|
|
||
|
|
def main():
|
||
|
|
with open("day10.txt", "rt") as input_file:
|
||
|
|
amap = [line.rstrip() for line in input_file.readlines()]
|
||
|
|
|
||
|
|
ast_positions = []
|
||
|
|
for x, line in enumerate(amap):
|
||
|
|
for y, value in enumerate(line):
|
||
|
|
if value == "#":
|
||
|
|
ast_positions.append((x, y))
|
||
|
|
|
||
|
|
best_vis = 0
|
||
|
|
for pos in ast_positions:
|
||
|
|
best_vis = max(best_vis, num_visible_asts(ast_positions, pos))
|
||
|
|
|
||
|
|
print("Best visibility is", best_vis)
|
||
|
|
|
||
|
|
def num_visible_asts(asts, ref):
|
||
|
|
count = 0
|
||
|
|
for ast in asts:
|
||
|
|
if ast[0] == ref[0] and ast[1] == ref[1]:
|
||
|
|
continue
|
||
|
|
if is_visible(asts, ref, ast):
|
||
|
|
count += 1
|
||
|
|
return count
|
||
|
|
|
||
|
|
def is_visible(asts, ref, target):
|
||
|
|
for ast in asts:
|
||
|
|
if ast[0] == ref[0] and ast[1] == ref[1]:
|
||
|
|
continue
|
||
|
|
if ast[0] == target[0] and ast[1] == target[1]:
|
||
|
|
continue
|
||
|
|
if is_on_line(ref, target, ast):
|
||
|
|
return False
|
||
|
|
return True
|
||
|
|
|
||
|
|
def is_on_line(a, b, p):
|
||
|
|
return math.isclose(dist(a, b), dist(a, p) + dist(b, p))
|
||
|
|
|
||
|
|
def dist(a, b):
|
||
|
|
return math.sqrt((a[0] - b[0]) ** 2 + (a[1] - b[1]) ** 2)
|
||
|
|
|
||
|
|
|
||
|
|
if __name__ == "__main__":
|
||
|
|
main()
|