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

 

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Funciones Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Para no modificar la secuencia de las operaciones 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
Modificación de la secuencia de operaciones 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
Particionamiento operaciones 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)
Clasificación de las operaciones (en rangos 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
Las operaciones binarias de búsqueda (en rangos 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
Conjunto de operaciones (en rangos 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
Operaciones del montón 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 operaciones 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
Operaciones 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)	(desde C++11)

Estas funciones encontrar el primer elemento de la [first, last) rango que satisface criterios específicos:

Original:

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

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1. find Busca un elemento igual a value

Original:

1. find searches for an element equal to value

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2. find_if Busca un elemento determinante para que p vuelve true

Original:

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

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3. find_if_not busca elemento para el que q predicado devuelve false

Original:

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

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Parámetros

first, last	-	la gama de elementos a 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 para comparar los elementos a 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 el elemento requerido 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 el elemento requerido 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 al primer elemento que satisface la condición o last si no se encuentra dicho elemento .

Original:

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

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Complejidad

A lo sumo last - first aplicaciones del predicado

Original:

At most last - first applications of the predicate

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Posible implementación

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; }

Si usted no tiene C + +11, un equivalente a std::find_if_not es utilizar std::find_if con el 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)); }

Ejemplo

El siguiente ejemplo busca un entero en un vector de enteros .

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

Ver también

adjacent_find	encuentra dos idénticas (o alguna otra relación) elementos adyacentes el uno al otro 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. (función de plantilla)
find_end	encuentra la última secuencia de elementos en un cierto rango 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. (función de plantilla)
find_first_of	searches for any one of a set of elements (función de plantilla)
mismatch	encuentra la primera posición donde dos rangos 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. (función de plantilla)
search	searches for a range of elements (función de plantilla)