#include <algorithm>
#include <iostream>
#include <set>

int main() {
    std::set<int> set = { 3, 1, 4, 1, 5, 9, 2, 6, 5 };
    std::for_each(set.cbegin(), set.cend(), [](int x) {
        std::cout << x << ' ';
    });
    std::cout << '\n';
}

#include <set>
#include <iostream>
 
int main() {
    std::set<int> numbers;
    std::cout << "Initially, numbers.empty(): " << numbers.empty() << '\n';
 
    numbers.insert(13317); 
    numbers.insert(3);
    numbers.insert(2);
    std::cout << "After adding elements, numbers.empty(): " << numbers.empty() << '\n';
    
    std::for_each(numbers.cbegin(), numbers.cend(), [](int x) {
    std::cout << x << ' ';
  	});
    
    numbers.emplace(1);
    
    numbers.erase(1);
    
    uint32_t size = numbers.size();
    std::cout << "nums contains " << size << " elements.\n";
    
    auto search = numbers.find(2);
    if (search != numbers.end()) {
        std::cout << "Found " << (*search) << '\n';
    } else {
        std::cout << "Not found\n";
    }
    
    numbers.clear();
	return 0;
}

#include <map>
#include <iostream>
#include <utility>
 
int main(void) {
    std::map<int,int> numbers;
    
    numbers.emplace(42, 13);
    numbers.emplace_hint(41, 12);
    numbers.insert(std::make_pair(13317, 123)); 
    std::cout << "After adding elements, numbers.empty(): " << numbers.empty() << '\n';
    
    std::cout << "After elements, numbers.size(): " << numbers.size() << '\n';
    
    numbers.try_emplace(40, 10);

	numbers.erase(40);
	
    const auto count = std::erase_if(data, [](const auto& item) {
        auto const& [key, value] = item;
        return (key & 1) == 1;
    });
    std::cout << "Erase items with odd keys:\n" << data << '\n'
              << count << " items removed.\n";
    
    myMap.insert_or_assign("a", "apple");
    
	numbers.find(42);
	std::cout << "After elements, numbers.clear(): " << numbers.clear() << '\n';
	return 0;
}