public member function

std::set::empty

<set>
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

set::clear
Clear content (public member function)
set::erase
Erase elements (public member function)
set::size
Return container size (public member function)