Template:cpp/container/equal range unord

@1,2@ Returns a range containing all elements with key in the container. The range is defined by two iterators, the first pointing to the first element of the wanted range and the second pointing past the last element of the range. @3,4@ Returns a range containing all elements in the container with key equivalent to.

Return value
std containing a pair of iterators defining the wanted range. If there are no such elements, past-the-end (see end) iterators are returned as both elements of the pair.

Complexity
Average case linear in the number of elements with the key, worst case linear in the size of the container.