#include <iostream>
#include <algorithm>
#include <vector>

struct TRIPLE
{
  void operator()(int& i)
  {
    i*=3;
  }
};

template <typename T>
struct PRINTER
{
  void operator() (T& item)
  {
    std::cout << item << std::endl;
  }
};

int main(int argc, char** argv)
{
  std::vector<int> v;

  for (int i = 0; i < 10; i++)
  {
    v.push_back(i);
  }

  // print before
  std::for_each(v.begin(), v.end(), PRINTER<int>());

  // triple all the members
  std::for_each(v.begin(), v.end(), TRIPLE());

  std::cout << "++++++++++++++++++++++++++++++++++++++++++++++++++" << std::endl;

  // print after
  std::for_each(v.begin(), v.end(), PRINTER<int>());

  return 0;
}