61 lines
1.4 KiB
Python
61 lines
1.4 KiB
Python
from collections import defaultdict
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import astar
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def parse(file):
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return [
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tuple([int(x) for x in line.strip().split(',')])
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for line in file
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]
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def solve(file, N=71, T=1024):
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falling = parse(file)
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inf = float('inf')
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map = [[0]*N for _ in range(N)]
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map = defaultdict(lambda: inf)
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for i,p in enumerate(falling):
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map[p] = i
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sol = _solve(map, N, T)
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print(sol)
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print(len(sol[-1])-1)
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def _solve(map, N=71, T=1024):
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start = (0,0) # x,y,t
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def neighbors(n):
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x,y = n
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def push(x,y):
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if 0 <= x < N and 0 <= y < N:
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if T <= map[x,y]:
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out.append((1,(x,y)))
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out = []
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push(x+1,y)
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push(x,y+1)
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push(x-1,y)
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push(x,y-1)
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return out
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end = N-1, N-1
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def heuristic(n):
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return abs(end[0] - n[0]) + abs(end[1] - n[1])
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return astar.search(start, end, neighbors, heuristic)
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import math
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def solve2(file, N=71, T=1024):
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falling = parse(file)
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inf = float('inf')
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map = [[0]*N for _ in range(N)]
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map = defaultdict(lambda: inf)
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for i,p in enumerate(falling):
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map[p] = i
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sol = _solve(map, N, i+1)
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if math.isinf(sol[0]):
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print(p)
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break
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solve(open("sample1.in"), N=7, T=12)
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solve2(open("sample1.in"), N=7, T=12)
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solve(open("input"), N=71, T=1024)
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solve2(open("input"), N=71, T=1024)
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