find_last_not_of
size_type find_last_not_of (const basic_string& str, size_type pos = npos) const
{ return find_last_not_of (str.data(), pos, str.length()); }
size_type find_last_not_of (const charT* s, size_type pos, size_type n) const;
size_type find_last_not_of (const charT* s, size_type pos = npos) const
{ return find_last_not_of (s, pos, traits::length (s)); }
size_type find_last_not_of (charT c, size_type pos = npos) const;
str.erase(str.find_last_not_of(" \t") + 1);