#include <stdlib.h>
#include <iostream>
#include <math.h>

#include <vector>

#include <boost/thread/thread.hpp>
#include <boost/bind.hpp>

using namespace std;

// Compile with: g++ -g -lboost_thread mt_test.cpp

struct ThreadData {
  ThreadData(const vector<double>& vOne,
	     const double factor) :
    m_vOne(vOne),
    m_factor(factor),
    m_vTwo(vOne.size(), m_factor)
    {
      // empty
    }
  
  const vector<double>&   m_vOne;
  double                  m_factor;
  vector<double>          m_vTwo;
};
  
static void* doAdd(void* data)
{
  ThreadData* pData = static_cast<ThreadData*>(data);

  for(unsigned int nAt = 0; nAt < pData->m_vOne.size(); ++nAt)
    pData->m_vTwo[nAt] += pData->m_factor * pData->m_vOne[nAt]; 

  return NULL;
}


int main(void) {

  const int nThreads = 12;
  const int nRepetitions = 200;
  
  vector<double> vOne(1<<24, 1.0);
  
  for(int nAtRepetition = 0; nAtRepetition < nRepetitions; ++nAtRepetition) {

    cout << "Repetition no. " << nAtRepetition << endl;

    vector<ThreadData*> vpData(nThreads, static_cast<ThreadData*>(NULL));  
    boost::thread_group threads;
    
    for (int nAtThread = 0; nAtThread < nThreads; nAtThread++) {
      vpData[nAtThread] = new ThreadData(vOne, static_cast<double>(nAtThread+1) );
      if( threads.create_thread( boost::bind(&doAdd, static_cast<void*> (vpData[nAtThread])) ) == 0 )
   	throw std::exception();
    }
    
    threads.join_all();
    
    for (int nAtThread = 0; nAtThread < nThreads; nAtThread++) 
      delete vpData[nAtThread];
  }

  return 0;
}