vector::cbegin
Returns a const iterator that points to the first element in the range.
const_iterator cbegin() const;
Return Value
A const random-access iterator that points to the first element of the range, or the location just beyond the end of an empty range (for an empty range, cbegin() == cend()).
Remarks
cbegin is used for read-only access with const_iterators.
You can use this member function in place of the begin() member function to guarantee that the return value is const_iterator. Typically, it's used in conjunction with the auto type deduction keyword, as shown in the following example. In the example, consider Container to be a modifiable (non-const) container of any kind that supports begin() and cbegin().
auto i1 = Container.begin(); // i1 is Container<T>::iterator
auto i2 = Container.cbegin(); // i2 is Container<T>::const_iterator
Requirements
Header: <vector>
Namespace: std