std::minmax_element
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| Defined in header <algorithm>
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| template< class ForwardIt > std::pair<ForwardIt,ForwardIt> |
(1) | |
| template< class ForwardIt, class Compare > std::pair<ForwardIt,ForwardIt> |
(2) | |
Encuentra el más grande y el más pequeño elemento de la
[first, last) rango. La primera versión utiliza operator< para comparar los valores, la segunda versión utiliza la función de comparación dado comp .Original:
Finds the greatest and the smallest element in the range
[first, last). The first version uses operator< to compare the values, the second version uses the given comparison function comp.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.
Contenido |
[editar] Parámetros
| first, last | - | iteradores hacia adelante que definen el rango de examinar
Original: forward iterators defining the range to examine The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
| cmp | - | comparison function which returns true if if *a is less than *b. The signature of the comparison function should be equivalent to the following: bool cmp(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.
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[editar] Valor de retorno
un par formado por un iterador al elemento más pequeño como el primer elemento y un iterador al elemento más grande que la segunda. Devoluciones std::make_pair(first, first) si el rango está vacía. Si varios elementos son equivalentes para el elemento más pequeño, el iterador al elemento tal primero se devuelve. Si varios elementos son equivalentes para el elemento más grande, el iterador al elemento tal se devolverá el último .
Original:
a pair consisting of an iterator to the smallest element as the first element and an iterator to the greatest element as the second. Returns std::make_pair(first, first) if the range is empty. If several elements are equivalent to the smallest element, the iterator to the first such element is returned. If several elements are equivalent to the largest element, the iterator to the last such element is returned.
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[editar] Complejidad
En la mayoría de las aplicaciones max(floor(3/2(N−1)), 0) del predicado, donde N = std::distance(first, last) .
Original:
At most max(floor(3/2(N−1)), 0) applications of the predicate, where N = std::distance(first, last).
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[editar] Posible implementación
| First version |
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template<class ForwardIt> std::pair<ForwardIt, ForwardIt> minmax_element(ForwardIt first, ForwardIt last) { typedef typename std::iterator_traits<ForwardIt>::value_type value_t; return std::minmax_element(first, last, std::less<value_t>()); } |
| Second version |
template<class ForwardIt, class Compare> std::pair<ForwardIt, ForwardIt> minmax_element(ForwardIt first, ForwardIt last, Compare comp) { std::pair<ForwardIt, ForwardIt> result(first, first); if (first == last) return result; if (++first == last) return result; if (comp(*first, *result.first)) { result.second = result.first; result.first = first; } else { result.second = first; } while (++first != last) { ForwardIt i = first; if (++first == last) { if (comp(*i, *result.first)) result.first = i; else if (!(comp(*i, *result.second))) result.second = i; break; } else { if (comp(*first, *i)) { if (comp(*first, *result.first)) result.first = first; if (!(comp(*i, *result.second))) result.second = i; } else { if (comp(*i, *result.first)) result.first = i; if (!(comp(*first, *result.second))) result.second = first; } } } return result; } |
[editar] Ejemplo
#include <algorithm> #include <iostream> #include <vector> int main() { std::vector<int> v = { 3, 9, 1, 4, 2, 5, 9 }; auto result = std::minmax_element(v.begin(), v.end()); std::cout << "min element at: " << (result.first - v.begin()) << '\n'; std::cout << "max element at: " << (result.second - v.begin()) << '\n'; }
Output:
min element at: 2 max element at: 6
[editar] Ver también
| devuelve el elemento más pequeño de un rango Original: returns the smallest element in a 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) | |
| devuelve el elemento más grande de un rango Original: returns the largest element in a 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) | |
