Function main

cpp_20/020_span_front.cpp:6–15

#include <iterator>
#include <algorithm>
int main()
{
    std::vector<int> v{1,2,3,4,5};
    std::deque<int> d;
    std::copy(v.begin(), v.end(),
              std::front_insert_iterator<std::deque<int>>(d)); // or std::front_inserter(d)
    for(int n : d)
        std::cout << n << ' ';
    std::cout << '\n';
}