std::find_first_of
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| definiert in Header <algorithm>
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| template< class ForwardIt1, class ForwardIt2 > ForwardIt1 find_first_of( ForwardIt1 first, ForwardIt1 last, |
(1) | (bis C + +11) (seit C++11) |
| template< class ForwardIt1, class ForwardIt2, class BinaryPredicate > ForwardIt1 find_first_of( ForwardIt1 first, ForwardIt1 last, |
(2) | (bis C + +11) (seit C++11) |
[first, last) für jedes der Elemente im Bereich [s_first, s_last). Die erste Version verwendet operator== um die Elemente zu vergleichen, verwendet die zweite Version des gegebenen binären Prädikats p . [first, last) for any of the elements in the range [s_first, s_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 | ||
-InputIt must meet the requirements of InputIterator.
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-ForwardIt1 must meet the requirements of ForwardIterator.
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-ForwardIt2 must meet the requirements of ForwardIterator.
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[Bearbeiten] Rückgabewert
[first, last), die gleich einem Element, ausgewählt aus dem Bereich [s_first; s_last) ist. Wenn ein solches Element gefunden wird, wird zurückgegeben last .[first, last) that is equal to an element from the range [s_first; s_last). If no such element is found, last is returned.You can help to correct and verify the translation. Click here for instructions.
[Bearbeiten] Komplexität
(S*N) Vergleiche, wo S = distance(s_first, s_last) und N = distance(first, last) .(S*N) 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 InputIt, class ForwardIt> InputIt find_first_of(InputIt first, InputIt last, ForwardIt s_first, ForwardIt s_last) { for (; first != last; ++first) { for (ForwardIt it = s_first; it != s_last; ++it) { if (*first == *it) { return first; } } } return last; } |
| Second version |
template<class InputIt, class ForwardIt, class BinaryPredicate> InputIt find_first_of(InputIt first, InputIt last, ForwardIt s_first, ForwardIt s_last, BinaryPredicate p) { for (; first != last; ++first) { for (ForwardIt it = s_first; it != s_last; ++it) { if (p(*first, *it)) { return first; } } } return last; } |
[Bearbeiten] Beispiel
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{0, 2, 3, 25, 5}; std::vector<int> t{3, 19, 10, 2}; auto result = std::find_first_of(v.begin(), v.end(), t.begin(), t.end()); if (result == v.end()) { std::cout << "no elements of v were equal to 3, 19, 10 or 2\n"; } else { std::cout << "found a match at " << std::distance(v.begin(), result) << "\n"; } }
Output:
found a match at 1
[Bearbeiten] Siehe auch
| (C++11) |
Findet das erste Elemente, welches bestimmte Kriterien erfüllt (Funktions-Template) |
