Name

count_if function template — Counts the number of times a predicate returns true

Synopsis

template<typename InIter, typename Predicate>
  typename iterator_traits<InIter>::difference_type
    count_if(InIter first, InIter last, Predicate pred);

The count_if function template returns the number of elements in the range [first, last) for which pred(*iter) returns true.

Technical Notes

Complexity is linear: pred is called exactly last - first times.

See Also

count function template, find_if function template

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