public member function
<set>
iterator begin();
const_iterator begin() const;
iterator begin() noexcept;
const_iterator begin() const noexcept;
Return iterator to beginning
Returns an iterator referring to the first element in the multiset container.
Because multiset containers keep their elements ordered at all times, begin points to the element that goes first following the container's sorting criterion.
If the container is empty, the returned iterator value shall not be dereferenced.
Return Value
An iterator to the first element in the container.
If the multiset object is const-qualified, the function returns a const_iterator. Otherwise, it returns an iterator.
Member types iterator and const_iterator are bidirectional iterator types pointing to elements.
Example
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
|
// multiset::begin/end
#include <iostream>
#include <set>
int main ()
{
int myints[] = {42,71,71,71,12};
std::multiset<int> mymultiset (myints,myints+5);
std::multiset<int>::iterator it;
std::cout << "mymultiset contains:";
for (std::multiset<int>::iterator it=mymultiset.begin(); it!=mymultiset.end(); ++it)
std::cout << ' ' << *it;
std::cout << '\n';
return 0;
}
|
Output:
mymultiset contains: 12 42 71 71 71
|
Iterator validity
No changes.
Data races
The container is accessed (neither the const nor the non-const versions modify the container).
Concurrently accessing the elements of a multiset is safe.
Exception safety
No-throw guarantee: this member function never throws exceptions.
The copy construction or assignment of the returned iterator is also guaranteed to never throw.
See also
- multiset::end
- Return iterator to end (public member function
)
- multiset::rbegin
- Return reverse iterator to reverse beginning (public member function
)
- multiset::rend
- Return reverse iterator to reverse end (public member function
)