Safe overloading with std::equal

Since C++20, there is a safer way to overload std::equal:
template< class InputIt1, class InputIt2 >
constexpr bool equal( InputIt1 first1, InputIt1 last1,
                      InputIt2 first2, InputIt2 last2 );
Because if they are different lengths, it won't run past on either
side. In theory, they should always be the same length.

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: I1d25331521c1590b5f448f93b657f58f9f06d778
4 files changed