#include <iostream>
#include <queue>
#include <stack>

int main( ) {
   std::stack<int> pila;                // internamente std::deque (aunque pudo haber sido std::vector)
   pila.push(1);                        // internamente push_back
   pila.push(2);
   pila.push(3);
   std::cout << pila.top( ) << " ";     // internamente back
   pila.pop( );                         // internamente pop_back
   std::cout << pila.top( ) << "\n";

   std::queue<int> cola;                // internamente std::deque
   cola.push(1);                        // internamente push_back
   cola.push(2);
   cola.push(3);
   std::cout << cola.front( ) << " ";   // internamente front
   cola.pop( );                         // internamente pop_front
   std::cout << cola.front( ) << "\n";
}