#include <iostream>
#include <cmath>
#include <vector>
#include <iterator>
#include <algorithm>

using std::cout;
using std::cin;
using std::endl;
using std::vector;

inline double my_sqrt(int val)
{
    return std::sqrt((double)val);
}

int main(int argc, char* argv[])
{
    vector<unsigned int> V;

    std::copy( std::istream_iterator<unsigned int>(cin), std::istream_iterator<unsigned int>(), std::back_inserter(V));

    cout.precision(4);
    cout.setf(std::ios::fixed);

    std::transform(V.rbegin(), V.rend(), std::ostream_iterator<double>(cout, "\n"), my_sqrt);

    return 0;
}
What is wrong???