39 lines
688 B
Go
39 lines
688 B
Go
package datastructures
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import "container/heap"
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type HeapItem struct {
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Value any
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Priority int
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index int
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}
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type MinHeap []*HeapItem
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func (m MinHeap) Len() int { return len(m) }
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func (m MinHeap) Less(i, j int) bool { return m[i].Priority < m[j].Priority }
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func (m MinHeap) Swap(i, j int) {
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m[i], m[j] = m[j], m[i]
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m[i].index = i
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m[j].index = j
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}
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func (m *MinHeap) Push(x any) {
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*m = append(*m, x.(*HeapItem))
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}
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func (m *MinHeap) Pop() any {
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old := *m
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n := len(old)
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item := old[n-1]
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item.index = 0
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old[n-1] = nil
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*m = old[0 : n-1]
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return item
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}
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func (m *MinHeap) Update(item *HeapItem, priority int) {
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item.Priority = priority
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heap.Fix(m, item.index)
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}
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