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enumerate all pathes
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| #! /usr/bin/python3 | |
| from typing import * | |
| from dataclasses import dataclass | |
| @dataclass | |
| class Node: | |
| neighbours: List[int] | |
| tmp: Set[Tuple[int,...]] | |
| pathes: Set[Tuple[int,...]] | |
| def append_tuple(t: Tuple[int,...], value: int) -> Tuple[int, ...]: | |
| lst = list(t) | |
| lst.append(value) | |
| return tuple(lst) | |
| class state: | |
| data : List[Node] | |
| def __init__(self, adjacency_list: List[List[int]]): | |
| self.data = [] | |
| for node, neighbours in enumerate(adjacency_list): | |
| self.data.append(Node(neighbours, set(),set())) | |
| def step(self) -> None: | |
| for i, node in enumerate(self.data): | |
| pathes : List[Tuple[int, ...]] = [] | |
| for path in node.tmp: | |
| pathes.append(append_tuple(path, i)) | |
| node.pathes.update(pathes) | |
| node.tmp = set() | |
| for neighbour_index in node.neighbours: | |
| #print(f"adding from {i} to {neighbour_index}: {pathes}") | |
| neighbour = self.data[neighbour_index] | |
| neighbour.tmp.update(pathes) | |
| neighbour.tmp.add((i,)) | |
| def run(self, n: int) -> None: | |
| for _ in range(n): | |
| self.step() | |
| def finalize(self) ->None: | |
| for i, node in enumerate(self.data): | |
| for path in node.tmp: | |
| node.pathes.add(append_tuple(path, i)) | |
| node.tmp = set() | |
| def get_cycles(self, n: int) -> Generator[Tuple[int, ...],None, None] : | |
| for i, node in enumerate(self.data): | |
| for path in node.pathes: | |
| if len(path) == n and path[0] == i: | |
| yield path | |
| def main() -> None: | |
| graph = [[1,2],[2,3],[0,1],[0,3]] | |
| s = state(graph) | |
| s.run(8) | |
| s.finalize() | |
| for cycle in s.get_cycles(7): | |
| print(cycle) | |
| #print(s.data) | |
| if __name__ == "__main__": | |
| main() |
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