69 lines
1.3 KiB
Go
69 lines
1.3 KiB
Go
//go:build !solution
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package lrucache
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import (
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"container/list"
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)
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type cacheEntry struct {
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key int
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value int
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}
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type lrucache struct {
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cap int
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data map[int]*list.Element
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recentEntries *list.List
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}
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func (c *lrucache) isFull() bool {
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return c.recentEntries.Len() == c.cap
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}
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func (c *lrucache) Get(key int) (int, bool) {
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e, ok := c.data[key]
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if !ok {
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return 0, false
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}
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entry := c.recentEntries.Remove(e).(cacheEntry)
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c.data[key] = c.recentEntries.PushBack(entry)
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return entry.value, true
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}
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func (c *lrucache) Set(key int, value int) {
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if c.cap == 0 {
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return
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}
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e, ok := c.data[key]
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if ok {
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c.recentEntries.Remove(e)
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c.data[key] = c.recentEntries.PushBack(cacheEntry{key, value})
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return
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}
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if c.isFull() {
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removed := c.recentEntries.Remove(c.recentEntries.Front()).(cacheEntry)
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delete(c.data, removed.key)
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}
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c.data[key] = c.recentEntries.PushBack(cacheEntry{key, value})
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}
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func (c *lrucache) Range(f func(key, value int) bool) {
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for e := c.recentEntries.Front(); e != nil; e = e.Next() {
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entry := e.Value.(cacheEntry)
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if !f(entry.key, entry.value) {
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return
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}
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}
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}
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func (c *lrucache) Clear() {
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for k := range c.data {
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delete(c.data, k)
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}
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c.recentEntries.Init()
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}
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func New(cap int) Cache {
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return &lrucache{cap, make(map[int]*list.Element), list.New()}
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}
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