43 lines
802 B
Plaintext
43 lines
802 B
Plaintext
'use strict'
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class LRUCache {
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constructor () {
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this.max = 1000
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this.map = new Map()
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}
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get (key) {
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const value = this.map.get(key)
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if (value === undefined) {
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return undefined
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} else {
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// Remove the key from the map and add it to the end
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this.map.delete(key)
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this.map.set(key, value)
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return value
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}
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}
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delete (key) {
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return this.map.delete(key)
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}
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set (key, value) {
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const deleted = this.delete(key)
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if (!deleted && value !== undefined) {
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// If cache is full, delete the least recently used item
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if (this.map.size >= this.max) {
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const firstKey = this.map.keys().next().value
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this.delete(firstKey)
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}
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this.map.set(key, value)
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}
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return this
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}
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}
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module.exports = LRUCache
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