#include <iostream>
#include <string>
#include <thread>
#include <future>
#include <algorithm>
 
std::string get_str_letters(int n) {
using namespace std::literals;
std::string s(n, '\0');
std::generate_n(s.begin(), n, 
[]{ return rand() % 26 + 'A';} );
std::this_thread::sleep_for(3s);
 
return s;
}
std::string get_str_digits(int n) {
using namespace std::literals;
std::string s(n, '\0');
std::generate_n(s.begin(), n, 
[]{ return rand() % 10 + '0';});
std::this_thread::sleep_for(3s);
return s;
}
int main() {
auto start = std::chrono::steady_clock::now();
 
auto ftr1=async(std::launch::deferred, get_str_letters,20);
auto ftr2=async(std::launch::deferred, get_str_digits,20);
 
// return değeri olan future<std::string> nesnesini alacağız.
auto s1 = ftr1.get(); // Buraya kadar çalıştırılan bir func yok.get funcı çalıştığı anda func kodu çalıştırılacak
auto s2 = ftr2.get(); // Burada da diğeri çalışacak
 
auto end = std::chrono::steady_clock::now();
 
std::cout << std::chrono::duration<double>(end-start).count() << " saniye\n";
std::cout << s1 + s2 << "\n";
}
 
 

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