“Найти с хэш -набором” Ответ

Найти с хэш -набором

#include <unordered_set>
#include <string>
#include <iostream>

int main() {
  std::unordered_set<std::string> planets{
    {"Venus"},
    {"Earth"},
    {"Mars"},
  };

  auto it = planets.find("Earth");
  if (it != planets.end()) {
    std::cout << *it << "\n";
  } else {
    std::cout << "No such planet.\n";
  }

  it = planets.find("PlanetX");
  if (it != planets.end()) {
    std::cout << *it << "\n";
  } else {
    std::cout << "No such planet.\n";
  }
}