std::find, std::find_if, std::find_if_not

 

C++

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Conceitos

Biblioteca de utilitários

Biblioteca cordas

Recipientes biblioteca

Biblioteca algoritmos

Biblioteca iteradores

Biblioteca numéricos

De entrada / saída da biblioteca

Biblioteca localizações

Biblioteca de expressões regulares(C++11)

Biblioteca operações atômica(C++11)

Biblioteca de suporte a discussão(C++11)

 

Biblioteca algoritmo

Funções Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Não modificar operações de seqüência 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
Modificando operações de seqüência 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
Particionamento operações 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)
Operações de classificação (em intervalos ordenados) 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
Binários operações de busca (em intervalos ordenados) 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
Definir operações (em intervalos ordenados) 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
Operações de pilha 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
Mínimo / máximo de operações 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
Operações numéricas 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 biblioteca 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 InputIt, class T > InputIt find( InputIt first, InputIt last, const T& value );	(1)
template<class InputIt, class UnaryPredicate > InputIt find_if( InputIt first, InputIt last,                  UnaryPredicate p );	(2)
template<class InputIt, class UnaryPredicate > InputIt find_if_not( InputIt first, InputIt last,                      UnaryPredicate q );	(3)	(a partir do C++ 11)

Estas funções encontrar o primeiro elemento na [first, last) intervalo que satisfaz critérios específicos:

Original:

These functions find the first element in the range [first, last) that satisfies specific criteria:

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1. find procura por um elemento igual a value

Original:

1. find searches for an element equal to value

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2. find_if procura um elemento para o qual predicado p retornos true

Original:

2. find_if searches for an element for which predicate p returns true

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3. find_if_not pesquisas de elemento para o qual predicado q retornos false

Original:

3. find_if_not searches for element for which predicate q returns false

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Parâmetros

first, last	-	a gama de elementos para examinar Original: the range of elements to examine The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
value	-	valor a comparar os elementos de Original: value to compare the elements to The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
p	-	unary predicate which returns ​true para o elemento desejado Original: for the required element The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. . The signature of the predicate function should be equivalent to the following:  bool pred(const Type &a); The signature does not need to have const&, but the function must not modify the objects passed to it. The type Type must be such that an object of type InputIt can be dereferenced and then implicitly converted to Type. ​
q	-	unary predicate which returns ​false para o elemento desejado Original: for the required element The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. . The signature of the predicate function should be equivalent to the following:  bool pred(const Type &a); The signature does not need to have const&, but the function must not modify the objects passed to it. The type Type must be such that an object of type InputIt can be dereferenced and then implicitly converted to Type. ​
Type requirements
- InputIt must meet the requirements of InputIterator.

Valor de retorno

Iterador para o primeiro elemento que satisfaça a condição ou last se nenhum elemento for encontrado.

Original:

Iterator to the first element satisfying the condition or last if no such element is found.

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Complexidade

No máximo last - first aplicações do predicado

Original:

At most last - first applications of the predicate

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Possível implementação

First version
template<class InputIt, class T> InputIt find(InputIt first, InputIt last, const T& value){for(; first != last;++first){if(*first == value){return first;}}return last;}
Second version
template<class InputIt, class UnaryPredicate> InputIt find_if(InputIt first, InputIt last, UnaryPredicate p){for(; first != last;++first){if(p(*first)){return first;}}return last;}
Third version
template<class InputIt, class UnaryPredicate> InputIt find_if_not(InputIt first, InputIt last, UnaryPredicate q){for(; first != last;++first){if(!q(*first)){return first;}}return last;}

Se você não tem C + 11, equivalente a std::find_if_not é usar std::find_if com o predicado negado.

Original:

If you do not have C++11, an equivalent to std::find_if_not is to use std::find_if with the negated predicate.

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template<class InputIt, class UnaryPredicate> InputIt find_if_not(InputIt first, InputIt last, UnaryPredicate q){return std::find_if(first, last, std::not1(q));}

Exemplo

O exemplo a seguir localiza um número inteiro em um vetor de inteiros .

Original:

The following example finds an integer in a vector of integers.

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#include <iostream>#include <algorithm>#include <vector>   int main(){int n1 =3;int n2 =5;   std::vector<int> v{0, 1, 2, 3, 4};   auto result1 = std::find(v.begin(), v.end(), n1);auto result2 = std::find(v.begin(), v.end(), n2);   if(result1 != v.end()){std::cout<<"v contains: "<< n1 <<'\n';}else{std::cout<<"v does not contain: "<< n1 <<'\n';}   if(result2 != v.end()){std::cout<<"v contains: "<< n2 <<'\n';}else{std::cout<<"v does not contain: "<< n2 <<'\n';}}

Output:

v contains: 3 v does not contain: 5

Veja também

adjacent_find	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)
find_end	encontra a última sequência de elementos em um determinado intervalo Original: finds the last sequence of elements in a certain range 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)
find_first_of	searches for any one of a set of elements (modelo de função)
mismatch	encontra a primeira posição em que dois intervalos diferentes Original: finds the first position where two ranges differ 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)
search	searches for a range of elements (modelo de função)