leetcode 460 LFU缓存

原题点这里

class Node implements Comparable<Node>{
    public int key;
    public int value;
    public int lastTime;
    public int fre;
    public Node(int key,int value,int lastTime){
        this.key=key;
        this.value=value;
        this.lastTime = lastTime;
        this.fre=1;
    }

    @Override
    public int compareTo(Node o) {

        if(this.fre!=o.fre){
            //System.out.println(this.key+"++++fre:"+this.fre);
            //System.out.println(o.key+"+++++fre"+o.fre);
            //System.out.println(Integer.compare(o.fre,this.fre));
            return Integer.compare(this.fre,o.fre);
        }
        //System.out.println(this.key+"---"+this.value);
        //System.out.println(o.key+"----"+o.value);
        //System.out.println(-Integer.compare(this.lastTime,o.lastTime));
        return Integer.compare(this.lastTime,o.lastTime);
    }

    public void setValue(int value,int lastTime) {
        this.value=value;
        this.lastTime=lastTime;
        this.fre++;
    }

    public int getValue(int lastTime) {
        this.lastTime=lastTime;
        this.fre++;
        return value;

    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Node node = (Node) o;
        return key == node.key;

    }

    @Override
    public int hashCode() {
        return Objects.hash(key, value);
    }
}
class LFUCache {
    public int capacity;
    public int time;
    public HashMap<Integer,Node> values;
    public TreeSet<Node> keys;
    public LFUCache(int capacity) {
        time=0;
        this.capacity=capacity;
        values = new HashMap<Integer, Node>();
        keys = new TreeSet<Node>();

    }

    public int get(int key) {
        if(capacity==0) return -1;
        if(values.containsKey(key)){
            Node oldN = values.get(key);
            keys.remove(oldN);
            int ans = oldN.getValue(++time);
            keys.add(oldN);
            return ans;
        }

        else return -1;

    }

    public void put(int key, int value) {
        if(capacity==0) return;
        if(values.containsKey(key)){
            Node oldN = values.get(key);
            keys.remove(oldN);
            oldN.setValue(value,++time);
            keys.add(oldN);

        }else{
            if(values.size()==this.capacity) {
                Node n = values.get(keys.first().key);
                values.remove(n.key);
                keys.remove(n);
            }

            Node s = new Node(key,value,++time);
            values.put(key,s);
            keys.add(s);

        }

    }

}

原文地址：https://www.cnblogs.com/superxuezhazha/p/12643859.html