#include <iostream>
#include <deque>
#include <algorithm>
#include <queue>

int main()
{
    using namespace std;
    deque<int> page{ 7, 0, 1, 2, 0, 3, 0, 4, 2, 3, 0, 3, 2, 1, 2, 0, 1, 7, 0, 1 };
    deque<int> frame;
    unsigned count = 0;
    while (!page.empty())
    {
        int nowUsed = page.front();
        page.pop_front();
        if (find(frame.begin(), frame.end(), nowUsed) != frame.end())
            continue;
        if (frame.size() == 3)
        {
            ++count;
            cout << frame.front() << ' ';
            frame.pop_front();
        }
        frame.push_back(nowUsed);
        cout << "缺页次数" << count << endl;
    }
}