korespodentni_elementi_niti

#include<iostream>
#include<thread>
#include <cmath>
#include <vector>
#include <future>
using namespace std;

typedef vector<double>::iterator c;

double f(c begin,c end,double *min){
    *min = *begin;
        for(; begin!=end; ++begin) {
            if(abs(*begin)< *min) *min= *begin;
            } return *min;
}

int main() {
   int n =3;
   vector<double>a = {2, 7, 5, 3, 0.8, 0.89, 1.2, 1, 4};
   double minimumi[n];
   thread niti[n];

   for (int i = 0; i < n; ++i){
        niti[i] = thread(f, a.begin()+ i* a.size()/3, a.begin()+ (i+1)*a.size()/3 ,&minimumi[i] );

   }

   for (int i = 0; i < n; ++i)
       niti[i].join();

double min;
        min= minimumi[0];

    for (int i = 0; i < n; ++i){
       if(minimumi[i]<min)min=minimumi[i];
}
cout<<min<<endl;
}