#include <iostream>
#include <queue>
#include <list>
int main(int argc, char *argv[])
{
std::list<int> v = {1, 2, 3, 4};
std::queue<int, std::list<int>> q(v);
q.push(5);
q.pop();
std::cout<<"Front: "<<q.front()<<std::endl;//2
std::cout<<"Back: "<<q.back()<<std::endl;//5
return 0;
}