C++ In a Nutshell

Name

copy_backward function template — Copies a range, starting at the end

Synopsis

template<typename BidiIter1, typename BidiIter2>
  BidiIter2 copy_backward(BidiIter1 first, BidiIter1 last, BidiIter2 result);

The copy_backward function template does the same thing as copy, but it works backward, starting at the element before last and copying elements toward first. The result iterator must point to one past the end of the destination and is decremented before copying each element. The return value is an iterator that points to the first element of the destination, as shown in Figure 13-3.

Figure 13-3. Copying a range backward

The result iterator cannot be in the source range [first, last), but other parts of the destination range can overlap with the source.

Technical Notes

The copy_backward function template assigns *(result - n) = *(last - n) for all n in the range [1, last - first].

Complexity is linear: exactly last - first assignments are performed.

See Also

copy function template, reverse_copy function template