41 lines
798 B
JavaScript
41 lines
798 B
JavaScript
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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