std::unordered_set<Key,Hash,KeyEqual,Allocator>::size (3) - Linux Manuals

std::unordered_set<Key,Hash,KeyEqual,Allocator>::size: std::unordered_set<Key,Hash,KeyEqual,Allocator>::size

NAME

std::unordered_set<Key,Hash,KeyEqual,Allocator>::size - std::unordered_set<Key,Hash,KeyEqual,Allocator>::size

Synopsis

size_type size() const noexcept; (since C++11)

Returns the number of elements in the container, i.e. std::distance(begin(), end()).

Parameters

(none)

Return value

The number of elements in the container.

Complexity

Constant.

Example

The following code uses size to display the number of elements in a std::unordered_set<int>:
// Run this code

  #include <unordered_set>
  #include <iostream>

  int main()
  {
      std::unordered_set<int> nums {1, 3, 5, 7};

      std::cout << "nums contains " << nums.size() << " elements.\n";
  }

Output:

  nums contains 4 elements.