#include <iostream>
#include <thread>
#include <vector>
#include <time.h>
#include <cmath>

using namespace std;

typedef vector<double>::const_iterator ci;
void f(ci begin, ci end, double &zbir)
{
    zbir = 0;
    for (ci it = begin; it != end; ++it)
        zbir += *it;

    cout << "Zbir je: " << zbir << endl;

}

int main()
{
    double zbir1 = 0, zbir2 = 0;
    int s = 0; // vector size
    thread t1, t2;
    vector<double> v;

    srand(time(NULL));
    for (int i=0; i<10000; i++)
        v.push_back(rand() % 100+1);

    s = v.size() / 2;
    t1 = thread(f,v.begin(), v.begin()+s, ref(zbir1));
    t2 = thread(f,v.begin()+s, v.end(), ref(zbir2));
    t1.join();
    t2.join();

    cout << "Ukupan zbir je: " << zbir1+zbir2 << endl;



    return 0;

}