64 lines
1.4 KiB
Python
Executable File
64 lines
1.4 KiB
Python
Executable File
#!/usr/bin/env python
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import math
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MAP = []
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START = (0, 0)
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END = (0, 0)
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DISTANCES = {}
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def possible(x, y):
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global MAP
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threshold = MAP[y][x] + 1 # Can't go higher than this, can always go lower
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points = [(x-1,y),(x+1,y),(x,y-1),(x,y+1)]
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out = []
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for (x,y) in points:
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if x < 0 or y < 0:
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continue
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if len(MAP) < y+1 or len(MAP[y]) < x+1:
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continue
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if MAP[y][x] > threshold:
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continue
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out.append((x,y))
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return out
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with open('input') as f:
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for y, line in enumerate(f):
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row = []
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for x, byte in enumerate(line.rstrip()):
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DISTANCES[(x,y)] = math.inf
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if byte == 'S':
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byte = 'a'
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START = (x,y)
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DISTANCES[START] = 0
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elif byte == 'E':
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byte = 'z'
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END = (x,y)
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row.append(ord(byte) - ord('a'))
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MAP.append(row)
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visited = set([])
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queue = [START]
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while len(queue) > 0:
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pos = queue.pop(0)
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visited.add(pos)
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for neighbour in possible(*pos):
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if neighbour == END:
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print(DISTANCES[pos] + 1)
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quit()
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if DISTANCES[neighbour] > DISTANCES[pos] + 1:
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DISTANCES[neighbour] = DISTANCES[pos] + 1
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if neighbour not in visited and neighbour not in queue:
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queue.append(neighbour)
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print("Couldn't find it!")
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