LRU算法隨筆

爲了方便自己背LRU的代碼···所以移植過來···

class LRUCache {

    Map<Integer,Integer> map ;
    int capacity;
    public LRUCache(int capacity) {
        map = new LinkedHashMap<>(capacity);
        this.capacity = capacity;
    }
    
    public int get(int key) {
        if(!map.containsKey(key)){
            return -1;
        }
        int value = map.get(key);
        map.remove(key);
        map.put(key,value);
        return value;
    }
    
    public void put(int key, int value) {
        if(map.containsKey(key)){
            map.remove(key);
            map.put(key,value);
        }else{
            if(map.size()==capacity){
                map.remove(map.keySet().iterator().next());
            }
            map.put(key,value);
        }
    }
}