sqrt.h

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/******************************************************************************
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Embedded Template Library.
https://github.com/ETLCPP/etl
https://www.etlcpp.com
 
Copyright(c) 2017 John Wellbelove
 
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#ifndef ETL_SQRT_INCLUDED
#define ETL_SQRT_INCLUDED
 
#include "platform.h"
#include "type_traits.h"
#include "constant.h"
 
#include <stddef.h>
 
namespace etl 
{
  //***************************************************************************
  //***************************************************************************
  template <size_t Value, size_t Root = 1>
  struct sqrt
  {
    typedef typename etl::conditional<((Root * Root) > Value), 
                                      etl::constant<intmax_t, Root - 1>,
                                      etl::sqrt<Value, Root + 1> >::type type;
 
#if ETL_USING_CPP11
    static constexpr size_t value = type::value;
#else
    enum
    {
      // Recursive definition.
      value = type::value
    };
#endif
  };
 
#if ETL_USING_CPP11
  template <size_t Value, size_t Root>
  constexpr size_t sqrt<Value, Root>::value;
#endif
 
#if ETL_USING_CPP17
  template <size_t Value, size_t Root = 1>
  inline constexpr size_t sqrt_v = sqrt<Value, Root>::value;
#endif
}
 
#endif