Generic Algorithms and Predicate Objects

• Function classes may be passed to generic algorithm as template parameter
• Commonly used to pass predicates such as LessThan

template <class I, class P> I g_max_element (I beg, I end, const P& p) { if (beg == end) return end; I max(beg); while (++beg != end) if (p(*max, *beg)) max = beg; return max; }

// usage: GreaterThan <sometype> gt; Vitr = g_max_element (V.Begin(), V.End(), gt) // min element of V = *Vitr Litr = g_max_element (L.Begin(), L.End(), gt) // min element of L = *Litr Ditr = g_max_element (D.Begin(), D.End(), gt) // min element of D = *Ditr Aitr = g_max_element (A, A + size, gt) // min element of A = *Aitr