47 lines
959 B
Go
47 lines
959 B
Go
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package fusenrender
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import "bytes"
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// An Slice is something we manage in a priority queue.
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type Slice[T any] struct {
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Key []byte // 键
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Value T // 值
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// 索引是在容器中的位置
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index int
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}
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// A PriorityQueue implements heap.Interface and holds Items.
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type PriorityQueue[T any] []*Slice[T]
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func (pq PriorityQueue[T]) Len() int { return len(pq) }
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func (pq PriorityQueue[T]) Less(i, j int) bool {
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// 使用字节数组键比较
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return bytes.Compare(pq[i].Key, pq[j].Key) < 0
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}
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func (pq PriorityQueue[T]) 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[T]) Push(x any) {
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n := len(*pq)
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item := x.(*Slice[T])
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item.index = n
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*pq = append(*pq, item)
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}
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func (pq *PriorityQueue[T]) Pop() any {
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old := *pq
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n := len(old)
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item := old[n-1]
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old[n-1] = nil
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item.index = -1
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*pq = old[0 : n-1]
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return item.Value
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}
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// 这样就可以支持基于[]byte键的优先队列操作了
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