C++实现LRU算法

#include <iostream>
#include <thread>
#include <mutex>
#include<condition_variable>
#include <atomic>
#include<unordered_map>
using namespace std;
class MYLRU {
private:
	struct node {
		int k;
		int v;
		node(int a, int b)
		{
			k = a;
			v = b;
		}
	};
public:
	MYLRU(int c):capity(c) {
	}
	int get(int key)
	{
		if (mymap.find(key) == mymap.end())
			return -1;
		mylist.splice(mylist.begin(), mylist, mymap[key]);
		return mymap[key]->v;
	}
	void set(int key, int value)
	{
		if (mymap.find(key) == mymap.end())
		{
			if (capity == mymap.size())
			{
				mymap.erase(mylist.back().k);
				mylist.pop_back();
			}
			mylist.push_front(node(key, value));
			mymap[key] = mylist.begin();
		}
		else
		{
			mylist.splice(mylist.begin(), mylist, mymap[key]);
			mylist.begin()->v = value;
		}
	}
private:
	int capity;
	unordered_map<int, list<node>::iterator>mymap;
	list<node>mylist;
};
int main()
{
	MYLRU mylru(3);
	while (1)
	{
		int flag,k,v;
		cin >> flag;
		if (flag == 1)
		{
			cin >> k >> v;
			mylru.set(k, v);
		}
		else
		{
			cin >> k;
			cout << mylru.get(k) << endl;
		}
	}
	return 0;
}