Org.BouncyCastle.Math.BigInteger.Gcd C# (CSharp) Метод

		public BigInteger Gcd(
			BigInteger value)
		{
			if (value.sign == 0)
				return Abs();

			if (sign == 0)
				return value.Abs();

			BigInteger r;
			BigInteger u = this;
			BigInteger v = value;

			while (v.sign != 0)
			{
				r = u.Mod(v);
				u = v;
				v = r;
			}

			return u;
		}

        /// <summary>Choose a random prime value for use with RSA</summary>
        /// <param name="bitlength">the bit-length of the returned prime</param>
        /// <param name="e">the RSA public exponent</param>
        /// <returns>a prime p, with (p-1) relatively prime to e</returns>
        protected virtual BigInteger ChooseRandomPrime(int bitlength, BigInteger e)
        {
            for (;;)
            {
                BigInteger p = new BigInteger(bitlength, 1, param.Random);

                if (p.Mod(e).Equals(BigInteger.One))
                    continue;

                if (!p.IsProbablePrime(param.Certainty))
                    continue;

                if (!e.Gcd(p.Subtract(BigInteger.One)).Equals(BigInteger.One))
                    continue;

                return p;
            }
        }