LRUCache.java

public class LRUCache {

    /*
    13.3
    */

    private int capacity;

    public LRUCache(int capacity) {
        this.capacity = capacity;
    }

    public Integer lookup(Integer key) {

        return 0;
    }

    public Integer insert(Integer key, Integer value) {

        return 0;
    }

    public Integer remove(Integer key) {

        return 0;
    }
}