//Purpose:
//  see if variadic reduce is possible using variadic templates.
//
//Result:
//  No, apparently b... is not an arg pack.
//

int add(int a,int b){return a+b;}

template<typename T, typename... U>
T fold(T (*op)(T,T), T z, U... a)
;

template<typename T>
T fold(T (*op)(T,T), T z, T a)
{ return op(z,a)
;}

template<typename T, typename... U>
T fold(T (*op)(T,T), T z, T a, U... b)
{ return op(z,fold(op,a,b...))
;}

#include <iostream>

int main(void)
{
    std::cout<<fold(add,1,2,3)<<"\n";
    std::cout<<fold(add,10,20,30)<<"\n";
    return 0;
}