template<class ForwardIterator, class T>
constexpr
void iota(ForwardIterator first, ForwardIterator last, T value);

#include <iostream>
#include <numeric>
#include <vector>

int main()
{
    std::vector<int> v;
    v.resize(5, 0);
    std::iota(std::begin(v), std::end(v), 0);

    for (auto el : v)
        std::cout << el << std::endl;

    return 0;
}

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