Description
count_if() counts elements in a sequence, according to a user-defined predicate that specifies which elements should be included in the count.
Declaration
template <class In, class Pred> iterator_traits<In>::difference_type count_if(In, In, Pred);
Concept
The sample counts all the negative integers in the vector, displaying a value of 2. It declares a local variable of type iterator_traits<int*>::difference_type to capture the return value from count_if. This special type is used to portably handle varying size requirements on different platforms.
Supported
Supported
Supported