public member function

std::list::empty

<list>
bool empty ( ) const;
Test whether container is empty
Returns whether the list 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 the content of a list container, use list::clear.

Parameters

none

Return Value

true if the container size is 0, false otherwise.

Example

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// list::empty
#include <iostream>
#include <list>
using namespace std;

int main ()
{
  list<int> mylist;
  int sum (0);

  for (int i=1;i<=10;i++) mylist.push_back(i);

  while (!mylist.empty())
  {
     sum += mylist.front();
     mylist.pop_front();
  }

  cout << "total: " << sum << endl;
  
  return 0;
}

The example initializes the content of the container to a sequence of numbers (form 1 to 10). It then pops the elements one by one until it is empty and calculates their sum.

Output:
total: 55

Complexity

Constant.

See also

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

C++