The "normal" way of deleting an element from a vector goes like this:
vec.erase(vec.begin() + index);
But in theory it's faster just to do this:
if (vec.size() > 1)
{
std::iter_swap(vec.begin() + index, vec.end() - 1);
vec.pop_back();
}
else
{
vec.clear();
}
Is there any reason to not use the latter?
The second case does not preserve the order of the elements in the vector. If this is a sorted vector or the order is important then you have just broken that in the second case where the first case would leave the order intact.