public member function
<vector>
std::vector::cbegin
const_iterator cbegin() const noexcept;
Return const_iterator to beginning
Returns a const_iterator pointing to the first element in the container.
A const_iterator is an iterator that points to const content. This iterator can be increased and decreased (unless it is itself also const), just like the iterator returned by vector::begin, but it cannot be used to modify the contents it points to, even if the vector object is not itself const.
If the container is empty, the returned iterator value shall not be dereferenced.
Return Value
A const_iterator to the beginning of the sequence.
Member type const_iterator is a random access iterator type that points to a const element.
Example
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// vector::cbegin/cend
#include <iostream>
#include <vector>
int main ()
{
std::vector<int> myvector = {10,20,30,40,50};
std::cout << "myvector contains:";
for (auto it = myvector.cbegin(); it != myvector.cend(); ++it)
std::cout << ' ' << *it;
std::cout << '\n';
return 0;
}
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Output:
myvector contains: 10 20 30 40 50
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Iterator validity
No changes.
Data races
The container is accessed.
No contained elements are accessed by the call, but the iterator returned can be used to access them. Concurrently accessing or modifying different elements 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
- vector::begin
- Return iterator to beginning (public member function)
- vector::cend
- Return const_iterator to end (public member function)
- vector::crbegin
- Return const_reverse_iterator to reverse beginning (public member function)