aecont.h

#ifndef AECONT_H
#define AECONT_H
#include <vector>
#include <algorithm>
template <typename T>
class alternating_endpoint_container: public std::vector<T>{
private:
    bool l = true;
public:
    alternating_endpoint_container():std::vector<T>(){
    }
    template< class Iter >
    alternating_endpoint_container( Iter first, Iter last ):std::vector<T>(){
        std::for_each( first, last, std::bind1st( std::mem_fun( &alternating_endpoint_container::insert ), this) );
    }
    void insert( T a ){
        ( ( l = !l ) )?( std::vector<T>::insert( std::vector<T>::end(), a ) ):( std::vector<T>::insert( std::vector<T>::begin(), a ) );
    }
    void erase(){
        ( ( l = !l ) )?( std::vector<T>::erase( std::vector<T>::begin() ) ):( std::vector<T>::erase( std::vector<T>::end() - 1 ) );
    }
};
#endif // AECONT_H