diff --git a/include/algorithm b/include/algorithm index 9c51284a..e8720ccf 100644 --- a/include/algorithm +++ b/include/algorithm @@ -3148,6 +3148,9 @@ is_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred) for (; __first != __last; ++__first) if (!__pred(*__first)) break; + if ( __first == __last ) + return true; + ++__first; for (; __first != __last; ++__first) if (__pred(*__first)) return false; diff --git a/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp b/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp index 6098a203..aa23d19a 100644 --- a/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp +++ b/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp @@ -17,6 +17,7 @@ #include #include "test_iterators.h" +#include "counting_predicates.hpp" struct is_odd { @@ -27,32 +28,50 @@ int main() { { const int ia[] = {1, 2, 3, 4, 5, 6}; + unary_counting_predicate pred((is_odd())); assert(!std::is_partitioned(input_iterator(std::begin(ia)), input_iterator(std::end(ia)), - is_odd())); + std::ref(pred))); + assert(pred.count() <= std::distance(std::begin(ia), std::end(ia))); } { const int ia[] = {1, 3, 5, 2, 4, 6}; + unary_counting_predicate pred((is_odd())); assert( std::is_partitioned(input_iterator(std::begin(ia)), input_iterator(std::end(ia)), - is_odd())); + std::ref(pred))); + assert(pred.count() <= std::distance(std::begin(ia), std::end(ia))); } { const int ia[] = {2, 4, 6, 1, 3, 5}; + unary_counting_predicate pred((is_odd())); assert(!std::is_partitioned(input_iterator(std::begin(ia)), input_iterator(std::end(ia)), - is_odd())); + std::ref(pred))); + assert(pred.count() <= std::distance(std::begin(ia), std::end(ia))); } { const int ia[] = {1, 3, 5, 2, 4, 6, 7}; + unary_counting_predicate pred((is_odd())); assert(!std::is_partitioned(input_iterator(std::begin(ia)), input_iterator(std::end(ia)), - is_odd())); + std::ref(pred))); + assert(pred.count() <= std::distance(std::begin(ia), std::end(ia))); } { const int ia[] = {1, 3, 5, 2, 4, 6, 7}; + unary_counting_predicate pred((is_odd())); assert( std::is_partitioned(input_iterator(std::begin(ia)), input_iterator(std::begin(ia)), - is_odd())); + std::ref(pred))); + assert(pred.count() <= std::distance(std::begin(ia), std::begin(ia))); + } + { + const int ia[] = {1, 3, 5, 7, 9, 11, 2}; + unary_counting_predicate pred((is_odd())); + assert( std::is_partitioned(input_iterator(std::begin(ia)), + input_iterator(std::end(ia)), + std::ref(pred))); + assert(pred.count() <= std::distance(std::begin(ia), std::end(ia))); } }