151 lines
3.2 KiB
Python
151 lines
3.2 KiB
Python
def read_file():
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with open("input_sample.txt","r") as f:
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seed = f.read().split('\n')
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# pad with floor to prevent out-of-bounds checks
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seats = []
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seats.append(list('.' * (len(seed[0])+2)))
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for row in seed:
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seats.append(list('.' + row + '.'))
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seats.append(list('.' * (len(seed[0])+2)))
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return seats
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def check_neighbors(state,i,j):
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a = state[i-1][j-1]
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b = state[i-1][j]
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c = state[i-1][j+1]
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d = state[i][j-1]
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e = state[i][j+1]
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f = state[i+1][j-1]
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g = state[i+1][j]
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h = state[i+1][j+1]
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return a+b+c+d+e+f+g+h
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from copy import deepcopy
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def find_steady_state(seats):
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height = len(seats)
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width = len(seats[0])
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state = deepcopy(seats)
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prev_state = deepcopy(seats)
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while True:
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for i in range(height):
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for j in range(width):
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cell = prev_state[i][j]
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if cell == ".":
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pass
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elif cell == "L":
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# check for no occupied seats
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neighbors = check_neighbors(prev_state,i,j)
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if "#" not in neighbors:
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state[i][j] = "#"
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else:
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state[i][j] = "L"
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elif cell == "#":
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# check for 4+ occupied seats
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neighbors = check_neighbors(prev_state,i,j)
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if neighbors.count("#") > 3:
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state[i][j] = "L"
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else:
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state[i][j] = "#"
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if state == prev_state:
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break
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prev_state = deepcopy(state)
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return state
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def part1(seats):
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final_state = find_steady_state(seats)
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output = ''
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for row in final_state:
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for character in row:
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output += character
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return output.count("#")
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def check_line_of_sight(state,i,j):
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height = len(state)
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width = len(state[0])
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a = "."
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n = 1
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while a == "." and i-n >= 0 and j-n >= 0:
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a = state[i-n][j-n]
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n += 1
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b = "."
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n = 1
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while b == "." and i-n >= 0:
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b = state[i-n][j]
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n += 1
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c = "."
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n = 1
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while c == "." and i-n >= 0 and j+n < width:
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c = state[i-n][j+n]
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n += 1
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d = "."
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n = 1
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while d == "." and j-n >= 0:
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d = state[i][j-n]
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n += 1
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e = "."
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n = 1
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while e == "." and j+n < width:
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e = state[i][j+n]
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n += 1
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f = "."
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n = 1
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while f == "." and i+n < height and j-n >= 0:
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f = state[i+n][j-n]
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n += 1
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g = "."
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n = 1
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while g == "." and i+n < height:
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g = state[i+n][j]
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n += 1
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h = "."
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n = 1
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while h == "." and i+n < height and j+n < width:
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h = state[i+n][j+n]
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n += 1
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return a+b+c+d+e+f+g+h
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def find_steady_state_2(seats):
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height = len(seats)
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width = len(seats[0])
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state = deepcopy(seats)
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prev_state = deepcopy(seats)
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while True:
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for i in range(height):
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for j in range(width):
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cell = prev_state[i][j]
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if cell == ".":
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pass
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elif cell == "L":
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# check for no occupied seats
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neighbors = check_line_of_sight(prev_state,i,j)
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if "#" not in neighbors:
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state[i][j] = "#"
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else:
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state[i][j] = "L"
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elif cell == "#":
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# check for 4+ occupied seats
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neighbors = check_line_of_sight(prev_state,i,j)
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if neighbors.count("#") > 4:
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state[i][j] = "L"
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else:
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state[i][j] = "#"
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if state == prev_state:
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break
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prev_state = deepcopy(state)
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return state
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def part2(seats):
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pass
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final_state = find_steady_state_2(seats)
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output = ''
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for row in final_state:
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for character in row:
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output += character
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return output.count("#")
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def main():
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seats = read_file()
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print(part1(seats), part2(seats))
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if __name__ == "__main__":
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main() |