#include <utility>
 
template<template<typename,typename>class checker, typename... Ts>
struct is_all : std::true_type {};
 
template<template<typename,typename>class checker, typename T0, typename T1, typename... Ts>
struct is_all<checker, T0, T1, Ts...> :
  std::integral_constant< bool, checker<T0, T1>::value && is_all<checker, T0, Ts...>::value>
{};
 
template<typename... Ts>
using is_all_same = is_all< std::is_same, Ts... >;
 
#include <iostream>
 
int main() {
    std::cout << is_all_same<int, int>::value << is_all_same<double, double, int>::value << is_all_same<int, int, int, int, int>::value << "\n";
}

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