37 lines
665 B
Go
37 lines
665 B
Go
package d2astar
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// A priorityQueue implements heap.Interface and holds Nodes. The
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// priorityQueue is used to track open nodes by rank.
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type priorityQueue []*node
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func (pq priorityQueue) Len() int {
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return len(pq)
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}
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func (pq priorityQueue) Less(i, j int) bool {
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return pq[i].rank < pq[j].rank
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}
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func (pq priorityQueue) Swap(i, j int) {
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pq[i], pq[j] = pq[j], pq[i]
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pq[i].index = i
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pq[j].index = j
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}
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func (pq *priorityQueue) Push(x interface{}) {
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n := len(*pq)
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no := x.(*node)
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no.index = n
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*pq = append(*pq, no)
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}
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func (pq *priorityQueue) Pop() interface{} {
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old := *pq
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n := len(old)
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no := old[n-1]
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no.index = -1
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*pq = old[0 : n-1]
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return no
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}
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