Reference
C Library
IOstream Library
Strings library
STL Containers
STL Algorithms
Miscellaneous
STL Containers
bitset
deque
list
map
multimap
multiset
priority_queue
queue
set
stack
vector
set
comparison operators
set::set
set::~set
member functions:
set::begin
set::clear
set::count
set::empty
set::end
set::equal_range
set::erase
set::find
set::get_allocator
set::insert
set::key_comp
set::lower_bound
set::max_size
set::operator=
set::rbegin
set::rend
set::size
set::swap
set::upper_bound
set::value_comp


set::empty

public member function
bool empty ( ) const;

Test whether container is empty

Returns whether the set container is empty, i.e. whether its size is 0.

This function does not modify the content of the container in any way. To clear its content, use member clear.

Parameters

none

Return Value

true if the container size is 0, false otherwise.

Example

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// set::empty
#include <iostream>
#include <set>
using namespace std;
int main ()
{
  set<int> myset;
  myset.insert(20);
  myset.insert(30);
  myset.insert(10);
  cout << "myset contains:";
  while (!myset.empty())
  {
     cout << " " << *myset.begin();
     myset.erase(myset.begin());
  }
  cout << endl;
  return 0;
}


Output:
myset contains: 10 20 30

Complexity

Constant.

See also