std::list::size

 

C++

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Regular expressions library (C++11)

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std::list

Member functions

list::list

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Element access

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list::begin list::cbegin (C++11)

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size_type size() const;

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

Exceptions

noexcept specification:  

noexcept

  (since C++11)

Complexity

Constant or linear (until C++11)

Constant (since C++11)

Example

The following code uses size to display the number of elements in a std::list<int>:

run this code

#include <list>
#include <iostream>
 
int main()
{
    std::list<int> nums {1, 3, 5, 7};
 
    std::cout << "nums contains " << nums.size() << " elements.\n";
}

Output:

nums contains 4 elements.

See also

empty	checks whether the container is empty (public member function)
max_size	returns the maximum possible number of elements (public member function)
resize	changes the number of elements stored (public member function)