72 lines
1.5 KiB
TypeScript
72 lines
1.5 KiB
TypeScript
export class LRUCache<K, V> {
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private maxSize: number;
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private cache: Map<K, V>;
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private accessOrder: K[];
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constructor(maxSize: number) {
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this.maxSize = maxSize;
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this.cache = new Map();
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this.accessOrder = [];
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}
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get(key: K): V | undefined {
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const value = this.cache.get(key);
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if (value !== undefined) {
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this.markAsUsed(key);
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}
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return value;
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}
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set(key: K, value: V): void {
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if (this.cache.has(key)) {
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this.cache.set(key, value);
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this.markAsUsed(key);
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} else {
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if (this.cache.size >= this.maxSize) {
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this.evictLeastUsed();
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}
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this.cache.set(key, value);
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this.accessOrder.push(key);
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}
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}
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has(key: K): boolean {
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return this.cache.has(key);
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}
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delete(key: K): boolean {
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if (this.cache.delete(key)) {
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this.removeFromAccessOrder(key);
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return true;
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}
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return false;
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}
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clear(): void {
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this.cache.clear();
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this.accessOrder = [];
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}
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get size(): number {
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return this.cache.size;
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}
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private markAsUsed(key: K): void {
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this.removeFromAccessOrder(key);
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this.accessOrder.push(key);
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}
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private removeFromAccessOrder(key: K): void {
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const index = this.accessOrder.indexOf(key);
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if (index > -1) {
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this.accessOrder.splice(index, 1);
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}
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}
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private evictLeastUsed(): void {
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if (this.accessOrder.length > 0) {
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const leastUsed = this.accessOrder.shift()!;
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this.cache.delete(leastUsed);
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}
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}
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} |