std::gcd(3)

💅 NAME 💅

std::gcd - std::gcd — yes bestie, that's the whole NAME line, and it's giving minimalist icon behavior 💅. This is the std::gcd(3) page from the C++ Standard Libary manual, and it's here to make greatest-common-divisor math feel like a main character moment 💖.

🌸 Synopsis 🌸

Defined in header <numeric>

template< class M, class N >                         (since C++17)
constexpr std::common_type_t<M, N> gcd( M m, N n );

It computes the greatest common divisor of the integers m and n.

If either M or N is not an integer type, or if either is (possibly cv-qualified) bool, the program is ill-formed.

If either |m| or |n| is not representable as a value of type std::common_type_t<M, N>, the behavior is undefined. 💀

🐚 Parameters 🐚

• m, n — integer values

🎀 Return value 🎀

If both m and n are zero, returns zero. Otherwise, returns the greatest common divisor of |m| and |n|.

🦋 Exceptions 🦋

Throws no exceptions. Not a single one. The drama-free icon we deserve ✨.

🌈 Notes 🌈

Feature-test macro deets, because the standard library loves receipts 🧾:

• Feature-test macro: __cpp_lib_gcd_lcm
• Value: 201606L
• Std: (C++17)
• Feature: std::gcd, std::lcm

🍓 Example 🍓

This is the code, bestie — run it and watch the static_asserts hit:

// Run this code

        #include <numeric>

        int main()
        {
            constexpr int p{2 * 2 * 3};
            constexpr int q{2 * 3 * 3};
            static_assert(2 * 3 == std::gcd(p, q));

            static_assert(std::gcd( 6,  10) == 2);
            static_assert(std::gcd( 6, -10) == 2);
            static_assert(std::gcd(-6, -10) == 2);

            static_assert(std::gcd( 24, 0) == 24);
            static_assert(std::gcd(-24, 0) == 24);
        }

👑 See also 👑

• lcm — computes the least common multiple of two integers (C++17) (function template)

mwah 💋 source/version: http://cppreference.com — dated 2024.06.10 — page std::gcd(3), signing off with a compile-time kiss 🫶✨