#include <numeric>

#include "./stack.h"

template <typename T>
class stack<T*> {
public:
  auto push(T* t) -> void { stack_.push_back(t); }
  auto top() -> T* { return stack_.back(); }
  auto pop() -> void { stack_.pop_back(); }
  auto size() const -> std::size_t { return stack_.size(); };
  auto sum() -> int{
    return std::accumulate(stack_.begin(),
          stack_.end(), 0, [] (int a, T *b) { return a + *b; });
  }
private:
  std::vector<T*> stack_;
};