46 lines
1.2 KiB
Go
46 lines
1.2 KiB
Go
// File: heap.go
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// Created Time: 2023-01-12
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// Author: Reanon (793584285@qq.com)
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package chapter_heap
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// In Go, building a max-heap can be done by implementing the heap.Interface
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// Implementing heap.Interface requires implementing sort.Interface as well
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type intHeap []any
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// Push function for heap.Interface, to push elements into the heap
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func (h *intHeap) Push(x any) {
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// Push and Pop use pointer receivers as parameters
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// Because they not only adjust the contents of the slice but also modify its length
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*h = append(*h, x.(int))
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}
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// Pop function for heap.Interface, to pop the top element of the heap
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func (h *intHeap) Pop() any {
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// Element to be popped is placed at the end
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last := (*h)[len(*h)-1]
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*h = (*h)[:len(*h)-1]
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return last
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}
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// Len function for sort.Interface
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func (h *intHeap) Len() int {
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return len(*h)
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}
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// Less function for sort.Interface
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func (h *intHeap) Less(i, j int) bool {
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// If implementing a min-heap, adjust to use less than sign
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return (*h)[i].(int) > (*h)[j].(int)
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}
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// Swap function for sort.Interface
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func (h *intHeap) Swap(i, j int) {
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(*h)[i], (*h)[j] = (*h)[j], (*h)[i]
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}
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// Top retrieves the top element of the heap
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func (h *intHeap) Top() any {
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return (*h)[0]
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}
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