//Purpose:
//  Explore how to minimize space taken by struct of
//  optionals.
//Reference:
//
//  http://article.gmane.org/gmane.comp.lib.boost.devel/209212
//
#include <boost/optional.hpp>
#include <iostream>

struct A {
    int a;
    double b;
    double c;
    std::string d;
};

struct B {
    boost::optional< int > a;
    boost::optional< double > b;
    boost::optional< double > c;
    boost::optional< std::string > d;
}; 

struct A_pairs {
    int a;
    bool ta;
    double b;
    bool tb;
    double c;
    bool tc;
    std::string d;
    bool td;
}; 

struct A_bools {
    int a;
    double b;
    double c;
    std::string d;
    
    bool ta;
    bool tb;
    bool tc;
    bool td;
    
}; 

struct bools_A {
    bool ta;
    bool tb;
    bool tc;
    bool td;
    
    int a;
    double b;
    double c;
    std::string d;
    
}; 

struct chars_A {
    char ta;
    char tb;
    char tc;
    char td;
    
    int a;
    double b;
    double c;
    std::string d;
    
}; 

int main(void)
{
    std::cout<<"sizeof(A)="<<sizeof(A)<<"\n";
    std::cout<<"sizeof(B)="<<sizeof(B)<<"\n";
    std::cout<<"sizeof(A_pairs)="<<sizeof(A_pairs)<<"\n";
    std::cout<<"sizeof(A_bools)="<<sizeof(A_bools)<<"\n";
    std::cout<<"sizeof(bools_A)="<<sizeof(bools_A)<<"\n";
    std::cout<<"sizeof(chars_A)="<<sizeof(chars_A)<<"\n";
    return 0;
}