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priority_queue.go
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priority_queue.go
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package mpb
import "container/heap"
var _ heap.Interface = (*priorityQueue)(nil)
type priorityQueue []*Bar
func (pq priorityQueue) Len() int { return len(pq) }
func (pq priorityQueue) Less(i, j int) bool {
// greater priority pops first
return pq[i].priority > pq[j].priority
}
func (pq priorityQueue) Swap(i, j int) {
pq[i], pq[j] = pq[j], pq[i]
pq[i].index = i
pq[j].index = j
}
func (pq *priorityQueue) Push(x interface{}) {
n := len(*pq)
bar := x.(*Bar)
bar.index = n
*pq = append(*pq, bar)
}
func (pq *priorityQueue) Pop() interface{} {
old := *pq
n := len(old)
bar := old[n-1]
old[n-1] = nil // avoid memory leak
bar.index = -1 // for safety
*pq = old[:n-1]
return bar
}