Acid
82 lines
1.4 KiB
Go
82 lines
1.4 KiB
Go
package graphs
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import (
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"datastructures/linear"
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)
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// DFS() -> Depth First traversal, returns ordered slice or nil if start point
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// is invalid
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func (graph *Graph[T]) DFS(start T) []T {
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// sanity check
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if _, ok := graph.adjList[start]; !ok {
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return nil
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}
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visited := make(map[T]bool, len(graph.adjList))
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ordered := make([]T, 0, graph.Order())
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stack := linear.Stack[T]{}
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stack.Push(start)
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visited[start] = true
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for stack.Size() > 0 {
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current, err := stack.Pop()
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if err != nil {
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break
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}
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ordered = append(ordered, current)
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for _, neighbor := range graph.adjList[current] {
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if !visited[neighbor] {
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visited[neighbor] = true
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stack.Push(neighbor)
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}
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}
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}
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return ordered
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}
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// BFS() -> Breadth First traversal start, returning the
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// vertices in visit order. Returns nil if start is not in the graph.
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func (graph *Graph[T]) BFS(start T) []T {
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// sanity check
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if _, ok := graph.adjList[start]; !ok {
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return nil
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}
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visited := make(map[T]bool, len(graph.adjList))
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ordered := make([]T, 0, graph.Order())
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queue := linear.Queue[T]{}
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queue.Push(start)
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visited[start] = true
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for queue.Size() > 0 {
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current, err := queue.Pop()
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if err != nil {
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break
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}
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ordered = append(ordered, current)
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for _, neighbor := range graph.adjList[current] {
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if !visited[neighbor] {
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visited[neighbor] = true
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queue.Push(neighbor)
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}
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}
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}
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return ordered
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}
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