60 lines
1.3 KiB
Python
60 lines
1.3 KiB
Python
import heapq
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import string
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chars = 'ES'+string.ascii_lowercase
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data = open("input").read().splitlines(False)
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data = [list(map(chars.index, line)) for line in data]
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#print(data)
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def get(x, y):
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return data[y][x]
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extra = []
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for x in range(len(data[0])):
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for y in range(len(data)):
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if get(x,y) == 1: # 'S'
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data[y][x] = chars.index('a')
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start = (x,y)
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elif get(x,y) == 0: # 'E'
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data[y][x] = chars.index('z')
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goal = (x,y)
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elif get(x,y) == 2: # 'a'
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# for part 2
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extra.append((x,y))
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def solve(part):
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q = [(0, start)]
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if part == 2:
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q.extend((0,p) for p in extra)
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done = {}
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while q:
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cost, (x,y) = heapq.heappop(q)
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if (x,y) in done:
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continue
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#print(x,y,cost)
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if (x,y) == goal:
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print('found', cost)
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break
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here = get(x,y)
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done[(x,y)] = cost
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n = []
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def check(x,y):
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if 0 <= y < len(data):
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if 0 <= x < len(data[y]):
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if get(x,y) <= here+1 and (x,y) not in done:
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n.append((cost+1, (x,y)))
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check(x-1, y)
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check(x+1,y)
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check(x, y-1)
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check(x, y+1)
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for p in n:
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heapq.heappush(q, p)
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solve(1)
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solve(2)
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