#include <stdio.h>
#include <stdlib.h>

#include <pthread.h>

#define NELEMENTS 1024
#define THREADS 4

// deklariram strukturo za prenašanje argumentov v niti
struct argumenti {
	int myID;         // ID posamezne niti
};

pthread_t thread[THREADS];

float vecA[NELEMENTS];
float vecB[NELEMENTS];
float vecC[NELEMENTS];

float dotProd;

// instance struktur - vsak anit dobi svojo
struct argumenti args[THREADS];

void *funkcijaNiti (void* arg){
  int mojID;
  struct argumenti *args ;
  args =  (struct argumenti *) arg;

  mojID = args->myID;

  for (int i = 0; i < NELEMENTS/THREADS; i++)
  {
    vecC[mojID*(NELEMENTS/THREADS)+i] = vecA[mojID*(NELEMENTS/THREADS)+i] * vecB[mojID*(NELEMENTS/THREADS)+i];
  }
  
}


int main () {
  // init vhodnih vektorjev:
  for (int i = 0; i < NELEMENTS; i++)
  {
    vecA[i] = 1.0;
    //*(vecA + i) = 1.0; 
    vecB[i] = 1.0;
  }
  
  // ustvarimo THREADS niti:
  for (int i = 0; i < THREADS; i++)
  {
    // inicializiraj IDje:
    args[i].myID = i;

    // ustvari niti:
    pthread_create( &thread[i],
                  NULL,
                  funkcijaNiti,
                  (void *) &args[i]);
  }
  
  for (int i = 0; i < THREADS; i++)
  {
    pthread_join(thread[i], NULL);
  }

  dotProd = 0.0;
  for (int i = 0; i < NELEMENTS; i++)
  {
    dotProd += vecC[i];
  }

  printf("Skalarni produkt = %f \n", dotProd);
  
 
  return 0;
}