40 lines
864 B
Go
40 lines
864 B
Go
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// Copyright (c) 2016 Bitfury Group Limited
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// Distributed under the MIT software license, see the accompanying
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// file LICENSE or http://www.opensource.org/licenses/mit-license.php
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package graph
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import "errors"
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func Path(v1, v2 Vertex, parent map[Vertex]Vertex) ([]Vertex, error) {
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path, err := ReversePath(v1, v2, parent)
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if err != nil {
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return nil, err
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}
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Reverse(path)
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return path, nil
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}
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func ReversePath(v1, v2 Vertex, parent map[Vertex]Vertex) ([]Vertex, error) {
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path := []Vertex{v2}
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for v2 != v1 {
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if v2 == parent[v2] {
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return nil, CyclicDataError
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}
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var ok bool
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v2, ok = parent[v2]
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if !ok {
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return nil, errors.New("Invalid key")
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}
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path = append(path, v2)
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}
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return path, nil
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}
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func Reverse(path []Vertex) {
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length := len(path)
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for i := 0; i < length/2; i++ {
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path[i], path[length-1-i] = path[length-1-i], path[i]
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}
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}
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