题解 | 机器翻译

#include <iostream>
#include <queue>
using namespace std;

int main() {
    int m, n;
    cin >> m >> n;
    int arr[1000] = { 0 };
    int w;
    queue<int> q;
    int y = 0;
    for (int i = 0; i < n; i++) 
    {
        cin >> w;
        if (arr[w]) continue;
        else 
        {
            y++;
            if (q.size() == m) 
            {
                arr[q.front()] = 0;
                q.pop();
            }
            q.push(w);
            arr[w] = 1;
        }
    }
    cout << y;
    return 0;
}
// 64 位输出请用 printf("%lld")