NKD

nkd.cpp

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>

std::vector<std::string> nkd;
int k, n;

int main()
{
    std::cin >> k >> n;
    for(int i = 0; i < n; i++) {
        std::string in;
        std::cin >> in;
        if (std::find(nkd.begin(), nkd.end(), in) != nkd.end()) {
            nkd.erase(std::find(nkd.begin(), nkd.end(), in));
            nkd.push_back(in);
        } else {
            if (nkd.size() >= k) {
                nkd.erase(nkd.end());
                nkd.push_back(in);
            } else {
                nkd.push_back(in);
            }
        }
    }

    std::cout << std::endl;
    for(int i = k - 1; i >= 0; i--) {
        std::cout << nkd[i] << std::endl;
    }

    return 0;
}