#include <vector>
#include <iostream>

using foo = std::vector<double>;

int main()
{
    std::vector<foo> Vfoo(3);

	Vfoo[0].resize(20);
    Vfoo[1].resize(1);
    
    for ( unsigned i = 0; i<20; ++i)
        Vfoo[2].push_back(3.14*i) ;

    std::cout << "Vfoo[0]:\n";    
    std::cout << "\tsizeof = " << sizeof(Vfoo[0]) << '\n' ;
    std::cout << "\telements stored = " << Vfoo[0].size() << '\n' ;
    std::cout << "\tcapacity = " << Vfoo[0].capacity() << "\n\n" ;
    
    std::cout << "Vfoo[1]:\n";
    std::cout << "\tsizeof = " << sizeof(Vfoo[1]) << '\n' ;
    std::cout << "\telements stored = " << Vfoo[1].size() << '\n' ;
    std::cout << "\tcapacity = " << Vfoo[1].capacity() << "\n\n" ;
    
    std::cout << "Vfoo[2]:\n";
    std::cout << "\tsizeof = " << sizeof(Vfoo[2]) << '\n' ;
    std::cout << "\telements stored = " << Vfoo[2].size() << '\n' ;
    std::cout << "\tcapacity = " << Vfoo[2].capacity() << '\n' ;
}