How to make a function accept certain parameters using templates and concepts

I want to write a function that accepts a certain number of parameters using constant templates, for example:

template<int count>
void foo(int... args) { ... }

foo<1>(0); // success
foo<2>(0); // error
foo<3>(0, 0, 0); // success

count in templates decides how many parameters it can accept.

I tried to write a prototype like this

template <int a, int b>
concept equal = (a == b);

template <int size>
void foo(int... args) requires equal<sizeof...(args), size>
{ ... }

and it fails to complie.
What is the correct way to do it, or is there a simplier method.

thanks very much

>Solution :

int... args is not the way to have int arg0, int arg1, .., int argN

You might do

template<int count, std::same_as<int> ...Ints>
void foo(Ints... args) requires (sizeof...(args) == count)
{
  // ...
}

Demo