std::chrono::year:: is_leap

From cppreference.com
C++
Utilities library
General utilities
Relational operators (deprecated in C++20)
Date and time utilities
Time point
(C++11)
(C++20)
Duration
(C++11)
Clocks
(C++20)
(C++20)
(C++20)
Time of day
(C++20) (C++20)
(C++20) (C++20)
(C++20)

Calendar
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
Time zone
(C++20)
(C++20)
(C++20) (C++20) (C++20) (C++20)
(C++20)
chrono I/O
(C++20)
C-style date and time
std::chrono::year
constexpr bool is_leap ( ) const noexcept ;
(since C++20)

Determines if * this represents a leap year in the proleptic Gregorian calendar .

* this represents a leap year if the stored year value

  • is divisible by 4 and not divisible by 100; or
  • is divisible by 400.

Return value

true if * this represents a leap year, otherwise false .

Example

Run this code 
#include <chrono>
#include <iostream>
 
int main()
{
    using namespace std::chrono_literals;
    for (const std::chrono::year y : {2020y, 2021y, 2000y, 3000y})
    {
        if (const int iy{static_cast<int>(y)}; y.is_leap())
            std::cout << iy << " is a leap year because it is divisible by "
                      << (iy % 400 == 0 ? "400\n" : "4 and not divisible by 100\n");
        else
            std::cout << iy << " is not a leap year\n";
    }
}

Output: 

2020 is a leap year because it is divisible by 4 and not divisible by 100
2021 is not a leap year
2000 is a leap year because it is divisible by 400
3000 is not a leap year
Retrieved from " https://en.cppreference.com/mwiki/index.php?title=cpp/chrono/year/is_leap&oldid=157518 "