public member function
<set>

std::multiset::size

size_type size() const;
size_type size() const noexcept;
Return container size
Returns the number of elements in the multiset container.

Parameters

none

Return Value

The number of elements in the container.

Member type size_type is an unsigned integral type.

Example

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
// multiset::size
#include <iostream>
#include <set>

int main ()
{
  std::multiset<int> myints;
  std::cout << "0. size: " << myints.size() << '\n';

  for (int i=0; i<10; i++) myints.insert(i);
  std::cout << "1. size: " << myints.size() << '\n';

  myints.insert (5);
  std::cout << "2. size: " << myints.size() << '\n';

  myints.erase (5);
  std::cout << "3. size: " << myints.size() << '\n';

  return 0;
}


Output:
0. size: 0
1. size: 10
2. size: 11
3. size: 9

Complexity

Constant.

Iterator validity

No changes.

Data races

The container is accessed.
Concurrently accessing the elements of a multiset is safe.

Exception safety

No-throw guarantee: this member function never throws exceptions.

See also