#include <iostream>
#include <list>
using namespace std;
//3,2,1
int main() {
    list<int> a;
    a.insert(a.begin(),1);
    cout << *(a.begin()) << endl;
    a.insert(a.begin(),3);
    cout << *a.begin()<< endl;
    a.insert(a.begin()++,2);
    list<int>::iterator iterator = a.begin();
    cout << *iterator << endl;
        return 0;
}