#pragma once

namespace at { namespace native { namespace {

template <typename T>
inline T data_index_init(T offset) {
  return offset;
}

template <typename T, typename... Args>
inline T data_index_init(T offset, T &x, const T &X, Args &&... args) {
  offset = data_index_init(offset, std::forward<Args>(args)...);
  x = offset % X;
  return offset / X;
}

inline bool data_index_step() {
  return true;
}

template <typename T, typename... Args>
inline bool data_index_step(T &x, const T &X, Args &&... args) {
  if (data_index_step(std::forward<Args>(args)...)) {
    x = ((x + 1) == X) ? 0 : (x + 1);
    return x == 0;
  }
  return false;
}

}}}  // namespace at::native::<anonymous>