#include<iostream>
#include<stack>
#include<vector>
#include<algorithm>


using namespace std;

int main(){
    stack<int> st;
    st.push(2);
    st.push(4);
    st.push(5);
    st.push(6);
    st.push(3);
    st.push(4);
    //for(auto elem:st) cout << elem << endl;
    int count = st.size();
    for (size_t i = 0; i < count; i++)
    {
        cout << st.top() << endl;
        st.pop();
    }



    vector<int> v1 {5,4,3,21,5,6,8};
    cout << "v1 unsorted: " << endl;
    for(auto elem:v1) cout << elem << " ";
    cout << endl;

    sort(v1.begin(), v1.end(), [&](int a, int b){return a > b;});
    cout << "v1 sorted: " << endl;
    for(auto elem:v1) cout << elem << " ";
    cout << endl;

    vector<int> v2;
    copy_if(v1.begin(), v1.end(), back_inserter(v2), [&](int a) {return a!=5;});
    cout << "v2" << endl;
    for(auto elem:v2) cout << elem << " ";
    cout << endl;

    vector<int> v3;
    copy(v2.begin(), v2.end(), back_inserter(v3));
    reverse(v3.begin(), v3.end());
    cout << "v3" << endl;
    for(auto elem:v3) cout << elem << " ";
    cout << endl;

    
}