pacont.h

#ifndef PACONT_H
#define PACONT_H
#include <vector>
template <typename T, typename F>
class predicate_alternating_container: public std::vector<T>{
        F f;
        typedef std::vector<T> B;
    public:
        predicate_alternating_container(){}
        template <typename P, typename Q>
        predicate_alternating_container( const predicate_alternating_container<P,Q>&  a ){for(int i=0;i<a.size();)insert(a[i++]);}
        void insert(T a){(f(B(B::begin(),B::end())))?(B::insert(B::begin(),a)):(B::insert(B::end()-1,a));}
        void erase(int i){B::erase(B::begin()+i);}
};
#endif // PACONT_H