68 lines
1.8 KiB
Python
68 lines
1.8 KiB
Python
VERBOSE = True
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def verbose(s = "", *args, **kwargs):
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if VERBOSE:
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print(s, *args, **kwargs)
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def get_input(sample = False, part = 1):
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with open(f'sample_p{part}' if sample else 'input', 'r') as f:
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return [line.strip() for line in f.readlines()]
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def dfs(start, end, I_V, E, visited, path, part):
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verbose(f"\t\tvisiting {I_V[start]} ({part = })")
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if start == end:
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verbose(f"found end")
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verbose(f"\t\tpath {list(map(lambda i: I_V[i], path))}")
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verbose("\t\t", end = "")
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for i, v in enumerate(visited):
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if v:
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verbose(f"{I_V[i]} visted {v}, ", end = "")
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verbose()
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return 1
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ret = 0
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for i, e in enumerate(E[start]):
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if e > 0 and visited[i] < part and visited.count(2) <= 2 :
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tmp_v = visited[:]
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if I_V[i] == I_V[i].lower():
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tmp_v[i] += 1
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# verbose(f"\tstarting search from {I_V[i]}")
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ret += dfs(i, end, I_V, E, tmp_v[:], path + [i], part)
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return ret
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def result(inp, part = 1):
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res = 0;
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# construct the graph with an adjacency matrix
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V_I = {}
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I_V = []
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for line in inp:
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nodes = line.split('-')
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for n in nodes:
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if n not in V_I:
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V_I[n] = len(I_V)
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I_V.append(n)
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E = [[0 for _ in range(len(V_I))] for _ in range(len(V_I))]
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for line in inp:
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nodes = line.split('-')
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n1, n2 = V_I[nodes[0]], V_I[nodes[1]]
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E[n1][n2] += 1
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E[n2][n1] += 1
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start = V_I["start"]
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verbose(f"{start = }")
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end = V_I["end"]
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verbose(f"{end = }")
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visited = [0] * len(V_I)
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visited[start] = 2
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res = dfs(start, end, I_V, E, visited, [start], part)
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return res
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if __name__ == "__main__":
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VERBOSE = False
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print(result(get_input(), part = 2))
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