73 lines
2 KiB
Python
73 lines
2 KiB
Python
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# y, x
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# j, i
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input = open("input", 'r')#.read().rstrip()
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data = []
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for line in input:
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data.append(list(line.rstrip()))
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def printenergized(pos, energized):
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for j, row in enumerate(data):
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for i, char in enumerate(row):
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if pos == (j,i):
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print("*", end="")
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elif (j, i) in energized:
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print("#", end="")
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else:
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print(char, end="")
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print()
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print()
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def beam(split_stack):
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assert(len(data) == len(data[0]))
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energized = set()
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prevpos = set()
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while len(split_stack) > 0:
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pos, dr = split_stack.pop()
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while min(pos) >= 0 and max(pos) < len(data):
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energized.add(pos)
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if pos+dr in prevpos:
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break
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else:
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prevpos.add(pos+dr)
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# printenergized(pos, energized)
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curr_space = data[pos[0]][pos[1]]
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if curr_space == "/":
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dr = (-dr[1], -dr[0])
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elif curr_space == "\\":
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dr = (dr[1], dr[0])
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elif curr_space == "-" and dr[0] != 0:
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split_stack.append(((pos[0], pos[1]+1),(0, 1)))
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split_stack.append(((pos[0], pos[1]-1),(0,-1)))
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break
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elif curr_space == "|" and dr[1] != 0:
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split_stack.append(((pos[0]+1, pos[1]),( 1,0)))
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split_stack.append(((pos[0]-1, pos[1]),(-1,0)))
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break
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pos = tuple(sum(elems) for elems in zip(pos,dr))
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return energized
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split_stack = [((0,0),(0,1))]
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energized = beam(split_stack)
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print(len(energized))
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energizes = []
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# Left & Right
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for dr, x in zip([1, -1], [0, len(data[0])-1]):
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for j in range(len(data)):
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split_stack = [((j,x),(0,dr))]
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energizes.append(len(beam(split_stack)))
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# Top & Bottom
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for dr, y in zip([1, -1], [0, len(data)-1]):
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assert(len(data[-1]) == len(data[0]))
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for i in range(len(data[0])):
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split_stack = [((y,i),(dr,0))]
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energizes.append(len(beam(split_stack)))
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print(max(energizes))
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