Insertion and Deletion

The insertion (insert and emplace) and deletion (erase) of elements in associative containers are similar to the rules of a std::vector. For associative container which can have a key only once, the insertion fails if the key is already in the container. Additionally, ordered associative containers support a special function ordAssCont.erase(key), which removes all pairs with the key and returns their number. See the usage of the function.