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Question #48 Difficulty: 2

According to the C++17 standard, what is the output of this program?

    #include <iostream>
#include <string>
#include <future>

int main() {
  std::string x = "x";

  std::async(std::launch::async, [&x]() {
    x = "y";
  std::async(std::launch::async, [&x]() {
    x = "z";

  std::cout << x;


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