alex1

#include <iostream>
#include <list>
#include <time.h>

using namespace std;

int main(void) {
    srand(time(NULL));

    int n, m;
    cin >> n >> m;
    list<int> a, b;

    cout << "\na:\n";
    for (int i = 0; i < n; ++ i) {
        int x = rand() % 10;
        a.push_back(x);
        cout << x << " ";
    }

    cout << "\n\nb:\n";
    for (int i = 0; i < m; ++ i) {
        int x = rand() % 10;
        b.push_back(x);
        cout << x << " ";
    }

    for (auto i = a.begin(); i != a.end();) {
        bool flag = true;
        for (auto j = b.begin(); j != b.end(); ++ j) {
            if (*i == *j)
                flag = false;
        }
        if (!flag) {
            a.erase(i);
            i = a.begin();
        }
        else
            ++ i;
    }

    cout << "\n\na(new):\n";
    for (auto i = a.begin(); i != a.end(); ++ i)
        cout << *i << " ";
    cout << "\n";
    return 0;
}