#include <iostream>
#include <fstream>
#include <climits>
#define Nmax 1000

using namespace std;

struct Stiva
{
    int st[Nmax];
    int top;

    void Init()
    {
        top = -1;
    }

    int Empty()
    {
        if(top == -1) return 1;
        return 0;
    }

    int Full()
    {
        if(top == Nmax - 1) return 1;
        return 0;
    }

    void Push(int x)
    {
        if(Full()) cout << "Stack Overflow!";
        else st[++top] = x;
    }

    void Pop()
    {
        if(!Empty()) top--;
    }

    int Top()
    {
        return st[top];
    }

    int Elem()
    {
        return top+1;
    }

    int Minim()
    {
        int m = INT_MAX;
        for(int i = 0; i <= top; i++)
            if(st[i] < m) m = st[i];
        return m;
    }
};

int main()
{
    int n, op;
    Stiva st;

    ifstream fin("stiva.in");
    ofstream fout("stiva.out");

    fin >> n;
    st.Init();

    for(int i = 1; i <= n; i++)
    {
        fin >> op;
        if(op == 1)
        {
            fin >> op;
            st.Push(op);
        }
        else if(op == 2)
        {
            if(st.Elem() > 0) fout << st.Top() << "\n";
            else fout << "Eroare 2!\n";
        }
        else if(op == 3) st.Pop();
        else if(op == 4) fout << st.Elem() << "\n";
        else fout << st.Minim() << "\n";
    }

    fin.close();
    fout.close();

    return 0;
}