std::random_shuffle, std::shuffle

 

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Algorithm Bibliothek

Funktionen Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Nicht-modifizierende Sequenz Operationen 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
Modifizierende Sequenz Operationen 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
Partitionierungsoperationen 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)
Sortierung Operationen (auf sortierten Bereiche) 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
Binary Suchaktionen (auf sortierten Bereiche) 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
Set-Operationen (auf sortierten Bereiche) 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
Heap-Operationen 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
Minimum / Maximum Operationen 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
Numerische Operationen 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-Bibliothek 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

 

definiert in Header <algorithm>
template<class RandomIt > void random_shuffle( RandomIt first, RandomIt last );	(1)
template<class RandomIt, class RandomFunc > void random_shuffle( RandomIt first, RandomIt last, RandomFunc& r ); template<class RandomIt, class RandomFunc > void random_shuffle( RandomIt first, RandomIt last, RandomFunc&& r );	(2)	(bis C + +11) (seit C++11)
template<class RandomIt, class URNG > void shuffle( RandomIt first, RandomIt last, URNG&& g );	(3)	(seit C++11)

Ordnet die Elemente in der gegebenen Bereich [first, last) so dass jede mögliche Permutation dieser Elemente gleiche Wahrscheinlichkeit des Auftretens hat .

Original:

Reorders the elements in the given range [first, last) such that each possible permutation of those elements has equal probability of appearance.

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1)

Der Zufallsgenerator ist die Implementierung definiert, aber die Funktion std::rand wird häufig verwendet .

Original:

The random number generator is implementation-defined, but the function std::rand is often used.

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2)

Der Zufallsgenerator ist die Funktion Objekt r .

Original:

The random number generator is the function object r.

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3)

Der Zufallsgenerator ist die Funktion Objekt g .

Original:

The random number generator is the function object g.

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Parameter

first, last	-	das Spektrum der Elemente Zufallswiedergabe Original: the range of elements to shuffle randomly The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
r	-	Funktionsobjekt Zurückführen eines zufällig ausgewählten Wertes vom Typ umwandelbar iterator_traits<RandomIt>::difference_type im Intervall [0, n), wenn als r(n) aufgerufen Original: function object returning a randomly chosen value of type convertible to iterator_traits<RandomIt>::difference_type in the interval [0,n) if invoked as r(n) The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
g	-	Funktionsobjekt Zurückführen eines zufällig ausgewählten Wertes vom Typ URNG::result_type im Intervall [g.min (), g.max ()] falls als g() (zB einem der einheitliche Zufallszahlengeneratoren aus <random>) aufgerufen Original: function object returning a randomly chosen value of type URNG::result_type in the interval [g.min(), g.max()] if invoked as g() (e.g. any of the uniform random number generators from <random>) The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Type requirements
- RandomIt must meet the requirements of ValueSwappable and RandomAccessIterator.
- URNG must meet the requirements of UniformRandomNumberGenerator.

Rückgabewert

(None)

Original:

(none)

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Komplexität

linear im Abstand first und last

Original:

linear in the distance between first and last

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Mögliche Implementierung

First version
template<class RandomIt, class RandomFunc>void random_shuffle(RandomIt first, RandomIt last, RandomFunc&& r){typenamestd::iterator_traits<RandomIt>::difference_type i, n; n = last - first;for(i = n-1; i >0;--i){usingstd::swap; swap(first[i], first[r(i+1)]);}}
Second version
template<class RandomIt, class UniformRandomNumberGenerator>void shuffle(RandomIt first, RandomIt last, UniformRandomNumberGenerator&& g){typedeftypenamestd::iterator_traits<RandomIt>::difference_type diff_t;typedeftypenamestd::make_unsigned<diff_t>::type udiff_t;typedeftypenamestd::uniform_int_distribution<udiff_t> distr_t;typedeftypename distr_t::param_type param_t;   distr_t D; diff_t n = last - first;for(diff_t i = n-1; i >0;--i){usingstd::swap; swap(first[i], first[D(g, param_t(0, i))]);}}

Beispiel

Der folgende Code zufällig mischt die Zahlen 1 .. 10:

Original:

The following code randomly shuffles the integers 1..10:

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#include <random>#include <algorithm>#include <iterator>#include <iostream>   int main(){std::vector<int> v ={1, 2, 3, 4, 5, 6, 7, 8, 9, 10};   std::random_device rd;std::mt19937 g(rd());   std::shuffle(v.begin(), v.end(), g);   copy(v.begin(), v.end(), std::ostream_iterator<int>(std::cout, " "));std::cout<<"\n";}

Mögliche Ausgang:

Original:

Possible output:

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8 6 10 4 2 3 7 1 9 5

Siehe auch

next_permutation	generates the next greater lexicographic permutation of a range of elements (Funktions-Template)
prev_permutation	generates the next smaller lexicographic permutation of a range of elements (Funktions-Template)