std::unique

 

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Funktionen Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Nicht-modifizierende Sequenz Operationen Original: Non-modifying sequence operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
all_of any_of none_of (C++11) (C++11) (C++11) for_each count count_if mismatch equal	find find_if find_if_not (C++11) find_end find_first_of adjacent_find search search_n
Modifizierende Sequenz Operationen Original: Modifying sequence operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
copy copy_if (C++11) copy_n (C++11) copy_backward move (C++11) move_backward (C++11) fill fill_n transform generate generate_n remove remove_if remove_copy remove_copy_if	replace replace_if replace_copy replace_copy_if swap swap_ranges iter_swap reverse reverse_copy rotate rotate_copy random_shuffle shuffle   (C++11) unique unique_copy
Partitionierungsoperationen Original: Partitioning operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
is_partitioned (C++11) partition partition_copy (C++11)	stable_partition partition_point (C++11)
Sortierung Operationen (auf sortierten Bereiche) Original: Sorting operations (on sorted ranges) The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
is_sorted (C++11) is_sorted_until (C++11) sort	partial_sort partial_sort_copy stable_sort nth_element
Binary Suchaktionen (auf sortierten Bereiche) Original: Binary search operations (on sorted ranges) The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
lower_bound upper_bound	binary_search equal_range
Set-Operationen (auf sortierten Bereiche) Original: Set operations (on sorted ranges) The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
merge inplace_merge includes	set_difference set_intersection set_symmetric_difference set_union
Heap-Operationen Original: Heap operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
is_heap is_heap_until (C++11) make_heap	push_heap pop_heap sort_heap
Minimum / Maximum Operationen Original: Minimum/maximum operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
max max_element min min_element minmax (C++11) minmax_element (C++11)	lexicographical_compare is_permutation (C++11) next_permutation prev_permutation
Numerische Operationen Original: Numeric operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
iota (C++11) accumulate inner_product	adjacent_difference partial_sum
C-Bibliothek Original: C library The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
qsort	bsearch

 

Defined in header <algorithm>
template< class ForwardIt > ForwardIt unique( ForwardIt first, ForwardIt last );	(1)
template< class ForwardIt, class BinaryPredicate > ForwardIt unique( ForwardIt first, ForwardIt last, BinaryPredicate p );	(2)

Entfernt alle aufeinander doppelte Elemente aus dem Bereich [first, last). Entfernen wird durch Verschieben des Bereichs, wenn in der Weise, dass Elemente, die gelöscht werden überschrieben werden benötigt getan. Nur das erste Element in jeder Gruppe von Elementen gleich bleibt. Die Elemente zwischen dem alten und dem neuen Ende oder Bereich sind intakt gelassen. Die erste Version verwendet operator== um die Elemente zu vergleichen, verwendet die zweite Version des gegebenen binären Prädikats p .

Original:

Removes all consecutive duplicate elements from the range [first, last). Removing is done by shifting the range when needed in such a way that elements to be erased are overwritten. Only the first element in each group of equal elements is left. The elements between the old and the new end or the range are left intact. The first version uses operator== to compare the elements, the second version uses the given binary predicate p.

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Parameter

first, last	-	der Bereich der Elemente zu verarbeiten Original: the range of elements to process The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
p	-	binary predicate which returns ​true if the elements should be treated as equal. The signature of the predicate function should be equivalent to the following:  bool pred(const Type1 &a, const Type2 &b); The signature does not need to have const &, but the function must not modify the objects passed to it. The types  Type1 and  Type2 must be such that an object of type ForwardIt can be dereferenced and then implicitly converted to both of them. ​
Type requirements
- ForwardIt must meet the requirements of ForwardIterator.
- The type of dereferenced ForwardIt must meet the requirements of MoveAssignable.

Rückgabewert

Forward-Iterator auf das neue Ende des Bereichs

Original:

Forward iterator to the new end of the range

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Mögliche Implementierung

First version
template<class ForwardIt> ForwardIt unique(ForwardIt first, ForwardIt last) { if (first == last) return last;   ForwardIt result = first; while (++first != last) { if (!(*result == *first)) { *(++result) = *first; } } return ++result; }
Second version
template<class ForwardIt, class BinaryPredicate> ForwardIt unique(ForwardIt first, ForwardIt last, BinaryPredicate p) { if (first == last) return last;   ForwardIt result = first; while (++first != last) { if (!p(*result, *first)) { *(++result) = *first; } } return ++result; }

Beispiel

Der folgende Code entfernt alle aufeinanderfolgenden gleichwertige Elemente aus einem Vektor von ganzen Zahlen .

Original:

The following code removes all consecutive equivalent elements from a vector of integers.

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#include <iostream>
#include <algorithm>
#include <vector>
 
int main() 
{
    std::vector<int> v{1, 2, 2, 2, 3, 3, 2, 2, 1};
    std::vector<int>::iterator last;
 
    last = std::unique(v.begin(), v.end()); // 1 2 3 2 1 3 2 2 1
                                            //           ^
    for (std::vector<int>::iterator it = v.begin(); it != last; ++it) {
        std::cout << *it << " ";
    }
    std::cout << "\n";
}

Output:

1 2 3 2 1

Komplexität

linear im Abstand first und last

Original:

linear in the distance between first and last

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Siehe auch

adjacent_find	findet zwei identischen (oder eine andere Beziehung) Elemente einander benachbart Original: finds two identical (or some other relationship) items adjacent to each other The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Funktions-Template)
unique_copy	erstellt eine Kopie von einigen Reihe von Elementen, die keine Folge Duplikate enthält Original: creates a copy of some range of elements that contains no consecutive duplicates The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Funktions-Template)