std::iota – cppreference.com

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definiert in Header `<numeric>`

`template< class ForwardIterator, class T > void iota( ForwardIterator first, ForwardIterator last, T value );`		(seit C++11)

Füllt den Bereich [first, last) mit sequentiell steigenden Werten, beginnend mit value und wiederholt Auswertung ++value .

Original:

Fills the range [first, last) with sequentially increasing values, starting with value and repetitively evaluating ++value.

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Equivalent Betrieb:

Original:

Equivalent operation:

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*(d_first)   = value;
*(d_first+1) = ++value;
*(d_first+2) = ++value;
*(d_first+3) = ++value;
...

Parameter

first, last	-	das Spektrum der Elemente Summe Original: the range of elements to sum The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
value	-	Anfangswert zu speichern, der Ausdruck + + Wert muss wohlgeformt sein Original: initial value to store, the expression ++value must be well-formed The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Rückgabewert

(None)

Original:

(none)

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Komplexität

Genau last - first Schritten und Aufgaben .

Original:

Exactly last - first increments and assignments.

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Mögliche Implementierung

template<class ForwardIterator, class T>
void iota(ForwardIterator first, ForwardIterator last, T value)
{
    while(first != last) {
        *first++ = value;
        ++value;
    }
}

Beispiel

Das folgende Beispiel gilt std::random_shuffle auf einen Vektor von Iteratoren zu einem std::list seit std::random_shuffle nicht zu einer std::list direkt angewendet werden. std::iota wird verwendet, um den Vektor zu schaffen .

Original:

The following example applies std::random_shuffle to a vector of iterators to a std::list since std::random_shuffle cannot be applied to an std::list directly. std::iota is used to create the vector.

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#include <numeric>
#include <algorithm>
#include <list>
#include <vector>
#include <iostream>

int main()
{
    std::list<int> l(10);
    std::iota(l.begin(), l.end(), -4);

    std::vector<std::list<int>::iterator> v(l.size());
    std::iota(v.begin(), v.end(), l.begin());

    std::random_shuffle(v.begin(), v.end());

    std::cout << "Contents of the list: ";
    for(auto n: l) {
        std::cout << n << ' ';
    }
    std::cout << '\n';

    std::cout << "Contents of the list, shuffled: ";
    for(auto i: v) {
        std::cout << *i << ' ';
    }
    std::cout << '\n';
}

Output:

Contents of the list: -4 -3 -2 -1 0 1 2 3 4 5
Contents of the list, shuffled: 0 -1 3 4 -4 1 -2 -3 2 5

Siehe auch


	weist eine Reihe von Elementen ein bestimmter Wert Original: assigns a range of elements a certain value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Funktions-Template) [edit]

	speichert das Ergebnis einer Funktion in einem Bereich Original: saves the result of a function 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) [edit]