下の★1を★2のように書きたいんだけど、どうやって書けばいいのか
教えてぇ

#include <iostream>

template <typename T>
auto Sum(T h)
{
  return h;
}

template <typename Head,typename... Rests>
auto Sum(Head head,Rests... rests)
{
  return head + Sum(rests...);
}

template<class F,class... Args>
auto
foo(F&& f,Args... args)
{
  return f(args...);
}

int main( int argc, char *argv[] )
{
  std::cout << foo(Sum<int,int,int>,1,2,3) << "\n";//★1
  //std::cout << foo(Sum,1,2,3) << "\n"; //★2

}