#include <iostream>
#include <vector>
#include <array>
template<class T,size_t N>
std::array<T,N> convert( const std::vector<T> & v )
{
//assert(v.size() == N);
std::array<T,N> r;
std::copy( v.begin(), v.end(), r.begin() );
return r;
}
int main() {
std::vector<double> v(4);
std::array<double,4> arr = convert<double,4>( v );
return 0;
}
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