dcsimg
Login | Register   
LinkedIn
Google+
Twitter
RSS Feed
Download our iPhone app
TODAY'S HEADLINES  |   ARTICLE ARCHIVE  |   FORUMS  |   TIP BANK
Browse DevX
Sign up for e-mail newsletters from DevX

By submitting your information, you agree that devx.com may send you DevX offers via email, phone and text message, as well as email offers about other products and services that DevX believes may be of interest to you. DevX will process your information in accordance with the Quinstreet Privacy Policy.


Tip of the Day
Language: C++
Expertise: Intermediate
Oct 17, 2000

WEBINAR:

On-Demand

Building the Right Environment to Support AI, Machine Learning and Deep Learning


The erase() Member Function of Associative Containers

The associative containers std::map, std::multimap, std::set, and std::multiset have the following three overloaded forms of the member function erase():

 
class map // simplified for brevity
{
public:
//..other members
 void erase(iterator position); // 1
 size_type erase(const key_type& x); // 2
 void erase(iterator first, iterator last); // 3
};

The first version takes an iterator pointing at an existing container element and erases it. For example, the following code erases the last element of the container:

 
employees.erase(employees.rbegin());

Remember that an element of an associative container is a pair of two values: a key and its associated value. The second version of erase() enables you to erase an element using its key. For example, suppose you have created the following map object:

 
std::map< int, std::string > employees;
//.. fill map
// erase the element whose first member equals 2
employees.erase(2); 

The third version of erase() deletes a sequence of elements whose bounds are indicated by the iterators first and last. For example, the following statement erases all the elements of a map:

 
employees.erase(employees.begin(), employees.end());

Of course, you can use the clear() member function to achieve the same effect because clear() simply calls erase(begin(), end());

Danny Kalev
 
Comment and Contribute

 

 

 

 

 


(Maximum characters: 1200). You have 1200 characters left.

 

 

Sitemap
Thanks for your registration, follow us on our social networks to keep up-to-date