#include <iostream>
#include <string>
#include <vector>
using namespace std;

struct ContainsIntegers
{
  virtual ~ContainsIntegers() = default;
  virtual int* begin() = 0;
  virtual int* end() = 0;
};

struct SingleValue : ContainsIntegers
{
  int value{ 0 };

  SingleValue() = default;

  explicit SingleValue(const int value)
    : value{value}
  {
  }


  int* begin() override { return &value; }
  int* end() override { return &value + 1; }
};

struct ManyValues : vector<int>, ContainsIntegers
{
  int* begin() override { return &(*this)[0]; }

  int* end() override { return &(*this)[size()]; }

  void add(const int value)
  {
    push_back(value);
  }
};

int sum(const vector<ContainsIntegers*> items)
{
  int result{ 0 };

  for (auto item : items)
  {
    for (auto value : *item)
    {
      result += value;
    }
  }

  return result;
}

#include "gtest/gtest.h"

//#include "helpers/iohelper.h"

//#include "exercise.cpp"

namespace
{
  class Evaluate : public testing::Test
  {
  };

  TEST_F(Evaluate, SimpleTest)
  {
    SingleValue single_value{ 11 };
    ManyValues other_values;
    other_values.add(22);
    other_values.add(33);
    ASSERT_EQ(66, sum({ &single_value, &other_values }));
  }

} // namespace