std::find_end
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definiert in Header <algorithm>
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template< class ForwardIt1, class ForwardIt2 > ForwardIt1 find_end( ForwardIt1 first, ForwardIt1 last, |
(1) | |
template< class ForwardIt1, class ForwardIt2, class BinaryPredicate > ForwardIt1 find_end( ForwardIt1 first, ForwardIt1 last, |
(2) | |
[s_first, s_last)
im Bereich [first, last)
. Die erste Version verwendet operator==
um die Elemente zu vergleichen, verwendet die zweite Version des gegebenen binären Prädikats p
. [s_first, s_last)
in the range [first, last)
. The first version uses operator==
to compare the elements, the second version uses the given binary predicate p
. You can help to correct and verify the translation. Click here for instructions.
Inhaltsverzeichnis |
[Bearbeiten] Parameter
first, last | - | das Spektrum der Elemente zu untersuchen
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. |
s_first, s_last | - | der Bereich der Elemente für
Original: the range of elements to search for The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
p | - | binary predicate which returns true if the elements should be treated as equal. The signature of the predicate function should be equivalent to the following: bool pred(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 | ||
-ForwardIt1 must meet the requirements of ForwardIterator .
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-ForwardIt2 must meet the requirements of ForwardIterator .
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[Bearbeiten] Rückgabewert
[s_first, s_last)
im Bereich [first, last)
.[s_first, s_last)
in range [first, last)
.You can help to correct and verify the translation. Click here for instructions.
last
zurückgegeben. (bis C + +11)last
is returned. (bis C + +11)You can help to correct and verify the translation. Click here for instructions.
[s_first, s_last)
leer oder, wenn keine solche Teilfolge gefunden wird, wird last
zurückgegeben. (seit C++11)[s_first, s_last)
is empty or if no such subsequence is found, last
is returned. (seit C++11)You can help to correct and verify the translation. Click here for instructions.
[Bearbeiten] Komplexität
S*(N-S+1)
Vergleiche, wo S = distance(s_first, s_last) und N = distance(first, last) .S*(N-S+1)
comparisons where S = distance(s_first, s_last) and N = distance(first, last).You can help to correct and verify the translation. Click here for instructions.
[Bearbeiten] Mögliche Implementierung
First version |
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template<class ForwardIt1, class ForwardIt2> ForwardIt1 find_end(ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last) { if (s_first == s_last) return last; ForwardIt1 result = last; while (1) { ForwardIt1 new_result = std::search(first, last, s_first, s_last); if (new_result == last) { return result; } else { result = new_result; first = result; ++first; } } return result; } |
Second version |
template<class ForwardIt1, class ForwardIt2, class BinaryPredicate> ForwardIt1 find_end(ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p) { if (s_first == s_last) return last; ForwardIt1 result = last; while (1) { ForwardIt1 new_result = std::search(first, last, s_first, s_last, p); if (new_result == last) { return result; } else { result = new_result; first = result; ++first; } } return result; } |
[Bearbeiten] Beispiel
find_end()
für zwei verschiedene Zahlenfolgen suchen .
find_end()
to search for two different sequences of numbers.
You can help to correct and verify the translation. Click here for instructions.
#include <algorithm> #include <iostream> #include <vector> int main() { std::vector<int> v{1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4}; std::vector<int>::iterator result; std::vector<int> t1{1, 2, 3}; result = std::find_end(v.begin(), v.end(), t1.begin(), t1.end()); if (result == v.end()) { std::cout << "subsequence not found\n"; } else { std::cout << "last subsequence is at: " << std::distance(v.begin(), result) << "\n"; } std::vector<int> t2{4, 5, 6}; result = std::find_end(v.begin(), v.end(), t2.begin(), t2.end()); if (result == v.end()) { std::cout << "subsequence not found\n"; } else { std::cout << "last subsequence is at: " << std::distance(v.begin(), result) << "\n"; } }
Output:
last subsequence is at: 8 subsequence not found
[Bearbeiten] Siehe auch
findet zwei identischen (oder eine andere Beziehung) Elemente einander benachbart 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. (Funktions-Template) | |
(C++11) |
Findet das erste Elemente, welches bestimmte Kriterien erfüllt (Funktions-Template) |
searches for any one of a set of elements (Funktions-Template) | |
Suchen nach einer Reihe aufeinanderfolgender Kopien eines Elements in einem Bereich Original: searches for a number consecutive copies of an 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. (Funktions-Template) |