integer.h

用C做的

		//! number of significant bytes = ceiling(BitCount()/8)
		unsigned int ByteCount() const;
		//! number of significant words = ceiling(ByteCount()/sizeof(word))
		unsigned int WordCount() const;

		//! return the i-th bit, i=0 being the least significant bit
		bool GetBit(size_t i) const;
		//! return the i-th byte
		byte GetByte(size_t i) const;
		//! return n lowest bits of *this >> i
		lword GetBits(size_t i, size_t n) const;

		//!
		bool IsZero() const {return !*this;}
		//!
		bool NotZero() const {return !IsZero();}
		//!
		bool IsNegative() const {return sign == NEGATIVE;}
		//!
		bool NotNegative() const {return !IsNegative();}
		//!
		bool IsPositive() const {return NotNegative() && NotZero();}
		//!
		bool NotPositive() const {return !IsPositive();}
		//!
		bool IsEven() const {return GetBit(0) == 0;}
		//!
		bool IsOdd() const	{return GetBit(0) == 1;}
	//@}

	//! \name MANIPULATORS
	//@{
		//!
		Integer&  operator=(const Integer& t);

		//!
		Integer&  operator+=(const Integer& t);
		//!
		Integer&  operator-=(const Integer& t);
		//!
		Integer&  operator*=(const Integer& t)	{return *this = Times(t);}
		//!
		Integer&  operator/=(const Integer& t)	{return *this = DividedBy(t);}
		//!
		Integer&  operator%=(const Integer& t)	{return *this = Modulo(t);}
		//!
		Integer&  operator/=(word t)  {return *this = DividedBy(t);}
		//!
		Integer&  operator%=(word t)  {return *this = Integer(POSITIVE, 0, Modulo(t));}

		//!
		Integer&  operator<<=(size_t);
		//!
		Integer&  operator>>=(size_t);

		//!
		void Randomize(RandomNumberGenerator &rng, size_t bitcount);
		//!
		void Randomize(RandomNumberGenerator &rng, const Integer &min, const Integer &max);
		//! set this Integer to a random element of {x | min <= x <= max and x is of rnType and x % mod == equiv}
		/*! returns false if the set is empty */
		bool Randomize(RandomNumberGenerator &rng, const Integer &min, const Integer &max, RandomNumberType rnType, const Integer &equiv=Zero(), const Integer &mod=One());

		bool GenerateRandomNoThrow(RandomNumberGenerator &rng, const NameValuePairs &params = g_nullNameValuePairs);
		void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &params = g_nullNameValuePairs)
		{
			if (!GenerateRandomNoThrow(rng, params))
				throw RandomNumberNotFound();
		}

		//! set the n-th bit to value
		void SetBit(size_t n, bool value=1);
		//! set the n-th byte to value
		void SetByte(size_t n, byte value);

		//!
		void Negate();
		//!
		void SetPositive() {sign = POSITIVE;}
		//!
		void SetNegative() {if (!!(*this)) sign = NEGATIVE;}

		//!
		void swap(Integer &a);
	//@}

	//! \name UNARY OPERATORS
	//@{
		//!
		bool		operator!() const;
		//!
		Integer 	operator+() const {return *this;}
		//!
		Integer 	operator-() const;
		//!
		Integer&	operator++();
		//!
		Integer&	operator--();
		//!
		Integer 	operator++(int) {Integer temp = *this; ++*this; return temp;}
		//!
		Integer 	operator--(int) {Integer temp = *this; --*this; return temp;}
	//@}

	//! \name BINARY OPERATORS
	//@{
		//! signed comparison
		/*! \retval -1 if *this < a
			\retval  0 if *this = a
			\retval  1 if *this > a
		*/
		int Compare(const Integer& a) const;

		//!
		Integer Plus(const Integer &b) const;
		//!
		Integer Minus(const Integer &b) const;
		//!
		Integer Times(const Integer &b) const;
		//!
		Integer DividedBy(const Integer &b) const;
		//!
		Integer Modulo(const Integer &b) const;
		//!
		Integer DividedBy(word b) const;
		//!
		word Modulo(word b) const;

		//!
		Integer operator>>(size_t n) const	{return Integer(*this)>>=n;}
		//!
		Integer operator<<(size_t n) const	{return Integer(*this)<<=n;}
	//@}

	//! \name OTHER ARITHMETIC FUNCTIONS
	//@{
		//!
		Integer AbsoluteValue() const;
		//!
		Integer Doubled() const {return Plus(*this);}
		//!
		Integer Squared() const {return Times(*this);}
		//! extract square root, if negative return 0, else return floor of square root
		Integer SquareRoot() const;
		//! return whether this integer is a perfect square
		bool IsSquare() const;

		//! is 1 or -1
		bool IsUnit() const;
		//! return inverse if 1 or -1, otherwise return 0
		Integer MultiplicativeInverse() const;

		//! modular multiplication
		CRYPTOPP_DLL friend Integer CRYPTOPP_API a_times_b_mod_c(const Integer &x, const Integer& y, const Integer& m);
		//! modular exponentiation
		CRYPTOPP_DLL friend Integer CRYPTOPP_API a_exp_b_mod_c(const Integer &x, const Integer& e, const Integer& m);

		//! calculate r and q such that (a == d*q + r) && (0 <= r < abs(d))
		static void CRYPTOPP_API Divide(Integer &r, Integer &q, const Integer &a, const Integer &d);
		//! use a faster division algorithm when divisor is short
		static void CRYPTOPP_API Divide(word &r, Integer &q, const Integer &a, word d);

		//! returns same result as Divide(r, q, a, Power2(n)), but faster
		static void CRYPTOPP_API DivideByPowerOf2(Integer &r, Integer &q, const Integer &a, unsigned int n);

		//! greatest common divisor
		static Integer CRYPTOPP_API Gcd(const Integer &a, const Integer &n);
		//! calculate multiplicative inverse of *this mod n
		Integer InverseMod(const Integer &n) const;
		//!
		word InverseMod(word n) const;
	//@}

	//! \name INPUT/OUTPUT
	//@{
		//!
		friend CRYPTOPP_DLL std::istream& CRYPTOPP_API operator>>(std::istream& in, Integer &a);
		//!
		friend CRYPTOPP_DLL std::ostream& CRYPTOPP_API operator<<(std::ostream& out, const Integer &a);
	//@}

private:
	friend class ModularArithmetic;
	friend class MontgomeryRepresentation;
	friend class HalfMontgomeryRepresentation;

	Integer(word value, size_t length);

	int PositiveCompare(const Integer &t) const;
	friend void PositiveAdd(Integer &sum, const Integer &a, const Integer &b);
	friend void PositiveSubtract(Integer &diff, const Integer &a, const Integer &b);
	friend void PositiveMultiply(Integer &product, const Integer &a, const Integer &b);
	friend void PositiveDivide(Integer &remainder, Integer &quotient, const Integer &dividend, const Integer &divisor);

	SecAlignedWordBlock reg;
	Sign sign;
};

//!
inline bool operator==(const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)==0;}
//!
inline bool operator!=(const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)!=0;}
//!
inline bool operator> (const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)> 0;}
//!
inline bool operator>=(const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)>=0;}
//!
inline bool operator< (const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)< 0;}
//!
inline bool operator<=(const CryptoPP::Integer& a, const CryptoPP::Integer& b) {return a.Compare(b)<=0;}
//!
inline CryptoPP::Integer operator+(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.Plus(b);}
//!
inline CryptoPP::Integer operator-(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.Minus(b);}
//!
inline CryptoPP::Integer operator*(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.Times(b);}
//!
inline CryptoPP::Integer operator/(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.DividedBy(b);}
//!
inline CryptoPP::Integer operator%(const CryptoPP::Integer &a, const CryptoPP::Integer &b) {return a.Modulo(b);}
//!
inline CryptoPP::Integer operator/(const CryptoPP::Integer &a, CryptoPP::word b) {return a.DividedBy(b);}
//!
inline CryptoPP::word    operator%(const CryptoPP::Integer &a, CryptoPP::word b) {return a.Modulo(b);}

NAMESPACE_END

NAMESPACE_BEGIN(std)
template<> inline void swap(CryptoPP::Integer &a, CryptoPP::Integer &b)
{
	a.swap(b);
}
NAMESPACE_END

#endif