std::set::clear(3)

💅 std::set::clear(3) 💅

okay bestie, welcome to std::set::clear(3) from the C++ Standard Libary manual — yes, “Libary” is literally in the header, and we are respecting the artifact 💖.

---

🌸 NAME 🌸

std::set::clear - std::set::clear

that’s the NAME section and honestly it ate. no notes. 💅

---

🦋 Synopsis 🦋

void clear();  (noexcept since C++11)

so here’s the tea: she erases all elements from the container. after this call, size() returns zero. iconic behavior, fr fr ✨.

she invalidates any references, pointers, and iterators referring to contained elements. but — and this is important — any past-the-end iterator remains valid 🫶.

---

🌸 Parameters 🌸

(none)

no parameters, no drama. she takes nothing and still clears the whole vibe check 💀.

---

💖 Return value 💖

(none)

returns nothing. she gives no return value, only closure. 🎀

---

🔥 Complexity 🔥

Linear in the size of the container, i.e., the number of elements.

that’s the whole complexity tea. periodt. ⭐

---

✨ Example ✨

// Run this code

#include <iostream>
#include <string_view>
#include <set>

void print_info(std::string_view rem, const std::set<int>& v)
{
    std::cout << rem << "{ ";
    for (const auto& value : v)
        std::cout << value << ' ';
    std::cout << "}\n";
    std::cout << "Size=" << v.size() << '\n';
}

int main()
{
    std::set<int> container{1, 2, 3};
    print_info("Before clear: ", container);
    container.clear();
    print_info("After clear: ", container);
}

🌈 Output 🌈

Before clear: { 1 2 3 }
Size=3
After clear: { }
Size=0

she really said “empty set, empty set, empty set” and the output ATE. 🍓

---

💀 Defect reports 💀

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

• DR: LWG 224; Applied to: C++98; Behavior as published: the complexity was log(size()) + N, but N was not defined; Correct behavior: corrected to 'linear in size()'.

history was made, paperwork was filed, and the complexity got corrected. 💅

---

👀 See also 👀

• erase — erases elements (public member function)

like, if clear() is the full reset, erase is the pick-and-choose girlypop. 🦋

---

kisses bestie, this page is from http://cppreference.com, dated 2024.06.10, and it’s literally titled std::set::clear(3). bye and slay 💜✨