std::experimental::ranges::find_end

From cppreference.com
< cpp‎ | experimental‎ | ranges
 
 
Technical specifications
Filesystem library (filesystem TS)
Library fundamentals (library fundamentals TS)
Library fundamentals 2 (library fundamentals TS v2)
Library fundamentals 3 (library fundamentals TS v3)
Extensions for parallelism (parallelism TS)
Extensions for parallelism 2 (parallelism TS v2)
Extensions for concurrency (concurrency TS)
Extensions for concurrency 2 (concurrency TS v2)
Concepts (concepts TS)
Ranges (ranges TS)
Reflection (reflection TS)
Mathematical special functions (special functions TR)
 
 
 
template< ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2, Sentinel<I2> S2,

          class Proj = ranges::identity,
          IndirectRelation<I2, projected<I1, Proj>> Pred = ranges::equal_to<> >
I1 find_end( I1 first1, S1 last1, I2 first2, S2 last2,

             Pred pred = Pred{}, Proj proj = Proj{} );
(1) (ranges TS)
template< ForwardRange R1, ForwardRange R2, class Proj = ranges::identity,

          IndirectRelation<ranges::iterator_t<R2>,
                           projected<ranges::iterator_t<R1>, Proj>> Pred = ranges::equal_to<> >
ranges::safe_iterator_t<R1> find_end( Rng1&& rng1, Rng2&& rng2,

                                      Pred pred = Pred{}, Proj proj = Proj{} );
(2) (ranges TS)
1) Searches for the last occurrence of the sequence [first2last2) in the range [first1last1) (after projection with proj).
2) Same as (1), but uses r1 as the first source range and r2 as the second source range, as if using ranges::begin(r1) as first1, ranges::end(r1) as last1, ranges::begin(r2) as first2, and ranges::end(r2) as last2.

Notwithstanding the declarations depicted above, the actual number and order of template parameters for algorithm declarations is unspecified. Thus, if explicit template arguments are used when calling an algorithm, the program is probably non-portable.

Parameters

first1, last1 - the range of elements to examine
r1 - the range of elements to examine
first2, last2 - the range of elements to search for
r2 - the range of elements to search for
pred - predicate to compare the elements
proj - projection to apply to the elements in the first range

Return value

Iterator to the beginning of last occurrence of the sequence [first2last2) in range [first1last1) (after projection with proj).

If [first2last2) is empty or if no such sequence is found, an iterator that compares equal to last1 is returned.

Complexity

At most S * (N - S + 1) applications of the predicate and projection, where S = last2 - first2 and N = last1 - first1.

Notes

The projection is only applied to the range [first1last1).

Possible implementation

template<ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2, Sentinel<I2> S2,
         class Proj = ranges::identity,
         IndirectRelation<I2, projected<I1, Proj>> Pred = ranges::equal_to<>>
I1 find_end(I1 first1, S1 last1, I2 first2, S2 last2,
            Pred pred = Pred{}, Proj proj = Proj{})
{
    I1 result = ranges::next(first1, last1);
    if (first2 == last2)
        return result;
    while (true)
    {
        I1 new_result = ranges::search(first1, last1, first2, last2, pred, proj);
        if (new_result == last1)
            break;
        else
        {
            result = new_result;
            first1 = result;
            ++first1;
        }
    }
    return result;
}

Example

See also

finds the last sequence of elements in a certain range
(function template)
searches for a range of elements
(function template)
returns true if one set is a subset of another
(function template)
finds the first two adjacent items that are equal (or satisfy a given predicate)
(function template)
finds the first element satisfying specific criteria
(function template)
searches for any one of a set of elements
(function template)
searches for a number consecutive copies of an element in a range
(function template)