std::is_sorted_until
Da cppreference.com.
<metanoindex/>
<tbody> </tbody>| Elemento definito nell'header <algorithm>
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template< class ForwardIt > ForwardIt is_sorted_until( ForwardIt first, ForwardIt last ); |
(1) | (dal C++11) |
template< class ForwardIt, class Compare > ForwardIt is_sorted_until( ForwardIt first, ForwardIt last, Compare comp ); |
(2) | (dal C++11) |
Esamina l'
[first, last) campo e trova l'inizio più vasta gamma di first in cui vengono ordinati gli elementi in ordine crescente. La prima versione della funzione utilizza operator< per confrontare gli elementi, il secondo utilizza la funzione di confronto dato comp.Original:
Examines the range
[first, last) and finds the largest range beginning at first in which the elements are sorted in ascending order. The first version of the function uses operator< to compare the elements, the second 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.
Parametri
| first, last | - | la gamma di elementi da esaminare
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. |
| comp | - | comparison function which returns true if the first argument is less than the second. The signature of the comparison function should be equivalent to the following:
The signature does not need to have |
| Type requirements | ||
-ForwardIt must meet the requirements of ForwardIterator.
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Valore di ritorno
Il limite superiore di inizio più vasta gamma di
first in cui vengono ordinati gli elementi in ordine crescente. Cioè, il it iteratore ultimo per il quale è ordinato [first, it) gamma.Original:
The upper bound of the largest range beginning at
first in which the elements are sorted in ascending order. That is, the last iterator it for which range [first, it) is sorted.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.
Complessità
lineare la distanza tra
first e lastOriginal:
linear in the distance between
first and lastThe 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.
Possibile implementazione
| First version |
|---|
template<class ForwardIt>
ForwardIt is_sorted_until(ForwardIt first, ForwardIt last)
{
if (first != last) {
ForwardIt next = first;
while (++next != last) {
if (*next < *first)
return next;
first = next;
}
}
return last;
}
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| Second version |
template< class ForwardIt, class Compare >
ForwardIt is_sorted_until(ForwardIt first, ForwardIt last,
Compare comp)
{
if (first != last) {
ForwardIt next = first;
while (++next != last) {
if (comp(*next, *first))
return next;
first = next;
}
}
return last;
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Esempio
#include <iostream>
#include <algorithm>
#include <iterator>
#include <random>
int main()
{
std::random_device rd;
std::mt19937 g(rd());
const int N = 6;
int nums[N] = {3, 1, 4, 1, 5, 9};
const int min_sorted_size = 4;
int sorted_size = 0;
do {
std::random_shuffle(nums, nums + N, g);
int *sorted_end = std::is_sorted_until(nums, nums + N);
sorted_size = std::distance(nums, sorted_end);
for (auto i : nums) std::cout << i << ' ';
std::cout << " : " << sorted_size << " initial sorted elements\n";
} while (sorted_size < min_sorted_size);
}
Possible output:
4 1 9 5 1 3 : 1 initial sorted elements
4 5 9 3 1 1 : 3 initial sorted elements
9 3 1 4 5 1 : 1 initial sorted elements
1 3 5 4 1 9 : 3 initial sorted elements
5 9 1 1 3 4 : 2 initial sorted elements
4 9 1 5 1 3 : 2 initial sorted elements
1 1 4 9 5 3 : 4 initial sorted elements