singlethread

#include <stdlib.h>
#include <time.h>

#include <iostream>
using namespace std;

#define LAYERS 100
#define NEURONS 100
#define INPUTS 100

unsigned long long getRealNanosecondsCount(timespec time)
{
    return (unsigned long long)time.tv_sec * 1000000000 + time.tv_nsec;
}

float sigmoid(float x)
{
  return x/100;
}

int main()
{
  struct timespec current_time;
  struct timespec next_time;

  srand((unsigned)time(0));

  // array of inputs weights
  float ** weights = new float * [LAYERS];
  for(int i=0;i<LAYERS;i++)
  {
      weights[i] = new float[NEURONS*INPUTS];

      for(int j=0;j<NEURONS*INPUTS;j++)
      {
        weights[i][j] = (float)rand() / RAND_MAX;
      }
  }
  //--------------------------
  // array of inputs values
  float * inputs = new float[INPUTS];
  for(int i=0;i<INPUTS;i++)
  {
    inputs[i] = (float)rand() / RAND_MAX;
  }
  //---------------------------
  // array of outputs
  float * outputs = new float[NEURONS];
  //---------------------------
  float * temp = new float[INPUTS*NEURONS];

  cout << "Memory for weights: " << sizeof(float)*LAYERS*NEURONS*INPUTS << endl;
  cout << "Memory for inputs: " << sizeof(float)*INPUTS << endl;
  cout << "Memory for outputs: " << sizeof(float)*NEURONS << endl;
  cout << "Memory for temp: " << sizeof(float)*NEURONS*INPUTS << endl;

  clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &current_time);

  for(int i=0;i<LAYERS;i++)
  {
    int k = 0;
    for(int j=0;j<INPUTS*NEURONS;j++)
    {
      temp[j] = inputs[k] * weights[i][j];

      k++;

      if(k >= INPUTS)
        k = 0;
    }

    for(int j=0;j<NEURONS;j++)
    {
      inputs[j] = 0;

      for(int l=0;l<INPUTS;l++)
      {
        inputs[j] += temp[j*INPUTS + l];
      }

      inputs[j] = sigmoid(inputs[j]);
    }
  }

  clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &next_time);

  for(int i=0;i<NEURONS;i++)
  {
    cout << inputs[i] << endl;
  }

  delete[] temp;
  delete[] outputs;
  delete[] inputs;

  for(int i=0;i<LAYERS;i++)
  {
      delete[] weights[i];
  }
  delete[] weights;

  cout << "Time: " << getRealNanosecondsCount(next_time) - getRealNanosecondsCount(current_time) << endl;

  return 0;
}