75 lines
1.7 KiB
Plaintext
75 lines
1.7 KiB
Plaintext
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#!/usr/bin/python3
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from pprint import pprint
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def read_area():
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area = []
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with open("input") as fh:
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for ln in fh:
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area.append(list(ln.strip()))
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return area
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def neighbours(area, i, j):
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count = 0
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for i1 in (-1, 0, 1):
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if i + i1 < 0:
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continue
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if i + i1 >= len(area):
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continue
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for j1 in (-1, 0, 1):
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if i1 == j1 == 0:
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continue
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if j + j1 < 0:
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continue
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if j + j1 >= len(area[i + i1]):
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continue
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n = 1
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while True:
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i2 = i + n * i1
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if not (0 <= i2 < len(area)):
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break
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j2 = j + n * j1
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if not (0 <= j2 < len(area[i2])):
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break
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if area[i2][j2] == "L":
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break
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if area[i2][j2] == "#":
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count += 1
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break
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n += 1
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return count
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def new_occ(area, i, j):
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if area[i][j] == ",":
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return "."
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if area[i][j] == "L" and neighbours(area, i, j) == 0:
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return "#"
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if area[i][j] == "#" and neighbours(area, i, j) >= 5:
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return "L"
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return area[i][j]
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def next_tick(area):
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new_area = []
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for i in range(len(area)):
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new_row = []
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for j in range(len(area[i])):
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new_row.append(new_occ(area, i, j))
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new_area.append(new_row)
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return new_area
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def count_occupied(area):
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sum = 0
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for row in area:
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for seat in row:
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sum += seat == "#"
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return sum
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area = read_area()
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while True:
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new_area = next_tick(area)
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if new_area == area:
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break
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area = new_area
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print(count_occupied(area))
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