fusen-render/priority_queue.go
2023-07-30 05:11:04 +08:00

47 lines
959 B
Go

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