An LRU cache in Java
Java interview exercise on Collections, difficulty 3 of 3. Solve it in the editor beside a worked example; the tests run the moment you do.
Write LruCache<K, V> with a capacity given to the constructor, get(key) returning the value or null, put(key, value), and size(). Both get and put make the key the most recently used; when a put would exceed the capacity, the least recently used entry is evicted. A LinkedHashMap in access order (the three-argument constructor) does most of the work.
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