#include <cassert>
#include <cstddef>
#include <vector>
#include <set>
#include <iterator>
#include <sstream>

int main()
{
    {
        std::set<int> v { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 };
        
        Block_Container<std::set<int>, 4> blocks { v };
        
        auto it { blocks.begin() };
        
        assert(( *it++ == std::vector<int>{ 1,  2,  3,  4 } ));
        assert(( *it++ == std::vector<int>{ 5,  6,  7,  8 } ));
        assert(( *it++ == std::vector<int>{ 9, 10, 11, 12 } ));

        // there aren't enough elements to split this evenly so the
        // "rest" is placed in the final block.
        assert(( *it++ == std::vector<int>{ 13 } ));
        
        assert( it == blocks.end() );
    }

    {
        std::vector<std::string> fruits {
            "Mango", "Pineapple", "Papaya",
            "Blueberries", "Blackberries", "Raspberries",
            "Pear", "Plum", "Peach",
            "Kiwi", "Passion fruit", "Lychee"
        };

        std::size_t offset { 0 };
        
        for (auto block : make_blocks<3>(fruits))
        {
            for (std::size_t i { 0 }; i < block.size(); ++i)
            {
                assert( block[i] == fruits[offset + i] );
            }
            offset += block.size();
        }

    }
}