std::unique
Da cppreference.com
 |
This page has been machine-translated from the English version of the wiki using Google Translate.
The translation may contain errors and awkward wording. Hover over text to see the original version. You can help to fix errors and improve the translation. For instructions click here. |
| Definido no cabeçalho <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) | |
Remove todos os elementos consecutivos duplicados do
[first, last) alcance. A remoção é realizada por deslocamento do intervalo, quando necessário, de tal forma que os elementos a serem apagados são substituídos. Apenas o primeiro elemento de cada grupo de elementos iguais é deixado. Os elementos entre o velho eo novo fim ou o intervalo são deixados intactos. A primeira versão utiliza operator== para comparar os elementos, a segunda versão usa o predicado binário dado 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.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Índice |
[editar] Parâmetros
| first, last | - | a gama de elementos ao processo
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. |
| Type requirements | ||
-ForwardIt must meet the requirements of ForwardIterator.
| ||
-The type of dereferenced ForwardIt must meet the requirements of MoveAssignable.
| ||
[editar] Valor de retorno
Transmitir iterador para o novo fim da amplitude
Original:
Forward iterator to the new end of the range
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
[editar] Possível implementação
| 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; } |
[editar] Exemplo
O código a seguir remove todos os elementos consecutivos equivalentes de um vetor de inteiros .
Original:
The following code removes all consecutive equivalent elements from a vector of integers.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
#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"; }
Saída:
1 2 3 2 1
[editar] Complexidade
linear, em que a distância entre
first e lastOriginal:
linear in the distance between
first and lastThe text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
[editar] Veja também
| encontra dois idênticos (ou algum outro relacionamento) itens adjacentes uns aos outros 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. (modelo de função) | |
| cria uma cópia de alguma gama de elementos que não contém duplicatas consecutivo 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. (modelo de função) | |
