std::prev

 

C++

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Biblioteca Iterator

Primitivas iterador Original: Iterator primitives The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
iterator_traits
input_iterator_tag output_iterator_tag forward_iterator_tag bidirectional_iterator_tag random_access_iterator_tag
iterator
Adaptadores iterador Original: Iterator adaptors The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
reverse_iterator
move_iterator (C++11) back_insert_iterator front_insert_iterator insert_iterator	make_move_iterator (C++11) back_inserter front_inserter inserter
Iteradores Stream Original: Stream iterators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
istream_iterator
ostream_iterator
istreambuf_iterator
ostreambuf_iterator
Operaciones iterador Original: Iterator operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
advance
distance
prev (C++11)
next (C++11)
Rango de acceso Original: Range access The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
begin (C++11)
end (C++11)

 

Defined in header <iterator>
template< class BidirIt > BidirIt prev( BidirIt it,               typename std::iterator_traits<BidirIt>::difference_type n = 1 );		(desde C++11)

Devuelva el predecesor de nth it iterador .

Original:

Return the nth predecessor of iterator it.

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Parámetros

it	-	un iterador Original: an iterator The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
n	-	número de it elementos deben ser descendidos Original: number of elements it should be descended The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Type requirements
- BidirIt must meet the requirements of BidirectionalIterator.

Valor de retorno

El predecesor de nth it iterador .

Original:

The nth predecessor of iterator it.

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Posible implementación

template<class BidirIt> BidirIt prev(BidirIt it, typename std::iterator_traits<BidirIt>::difference_type n = 1) { std::advance(it, -n); return it; }

Ejemplo

#include <iostream>
#include <iterator>
#include <vector>
 
int main() 
{
    std::vector<int> v{ 3, 1, 4 };
 
    auto it = v.end();
 
    auto pv = std::prev(it, 2);
 
    std::cout << *pv << '\n';
}

Output:

1

Ver también

next (C++11)	incrementar un iterador Original: increment an iterator The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función)
advance	avanza un iterador según distancia determinada Original: advances an iterator by given distance The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función)