自己实现LRU

这次是LeetCode146，这个代码做题可以通过但是有个问题就是最后设置的是默认析构，链表中的结点没有释放，造成了内存泄漏

struct node{
    int key, value;
    node *prev;
    node *next;
    node(){
        
    }
    node(int key, int value, node *prev = nullptr, node *next = nullptr){
        this->key = key;
        this->value = value;
        this->prev = prev;
        this->next = next;
    }
};
class LRUCache {
private:
    int size, k;
    node *head;
    node *tail;
    map<int, node*> mp;
    void movetohead(node* n){
        node* l = n->prev;
        node* r = n->next;
        l->next = r;
        r->prev = l;
        inserttohead(n);
    }
    void inserttohead(node* n){
        node* r = head->next;
        head->next = n;
        n->prev = head;
        n->next = r;
        r->prev = n;
    }
    node* removetail(){
        node* del = tail->prev;
        del->prev->next = tail;
        tail->prev = del->prev;
        return del;
    }
public:
    LRUCache(int capacity) {
        size = 0;
        k = capacity;
        head = new node();
        tail = new node();
        head->next = tail;
        tail->prev = head;
    }
    int get(int key) {
        if(mp.count(key)){
            movetohead(mp[key]);
            return mp[key]->value;
        }
        else return -1;
    }
    void put(int key, int value) {
        if(mp.count(key)){
            mp[key]->value = value;
            movetohead(mp[key]);
        }
        else{
            mp[key] = new node(key, value);
            inserttohead(mp[key]);
            size++;
            if(size > k) {
                node* del = removetail();
                size--;
                mp.erase(del->key);
                delete del;
            }
        }
    }
　　

　　~LRUCache(){

　　　　node *cur = head;

　　　　while(cur != tail){

            node *tmp = cur;

            cur = cur->next;

            cur->prev = nullptr;

            delete tmp;

　　　　}

　　}

};

/**
 * Your LRUCache object will be instantiated and called as such:
 * LRUCache* obj = new LRUCache(capacity);
 * int param_1 = obj->get(key);
 * obj->put(key,value);
 */