BigInteger Helper Class<\/p>\n\n\n\n
using System;\nusing System.Collections.Generic;\nusing System.Linq;\nusing System.Numerics;\nusing System.Text;\npublic static class BigIntegerHelper\n{\n private static readonly BigInteger Ten = new BigInteger(10);\n private static readonly BigInteger Three = new BigInteger(3);\n private static readonly BigInteger ONE = new BigInteger(1);\n private static readonly BigInteger Two = new BigInteger(2);\n public static BigInteger BigIntegerBase2(this string binaryValue)\n {\n BigInteger res = 0;\n if (binaryValue.Count(b => b == '1') + binaryValue.Count(b => b == '0') != binaryValue.Length) return res;\n foreach (var c in binaryValue)\n {\n res <<= 1;\n res += c == '1' ? 1 : 0;\n }\n return res;\n }\n public static BigInteger BigIntegerBase16(this string hexNumber)\n {\n if (string.IsNullOrEmpty(hexNumber))\n throw new Exception(\"Error: hexNumber cannot be either null or have a length of zero.\");\n if (!hexNumber.ContainsOnly(\"0123456789abcdefABCDEFxX\"))\n throw new Exception(\"Error: hexNumber cannot contain characters other than 0-9,a-f,A-F, or xX\");\n hexNumber = hexNumber.ToUpper();\n if (hexNumber.IndexOf(\"0X\", StringComparison.OrdinalIgnoreCase) != -1)\n hexNumber = hexNumber.Substring(2);\n var bytes = Enumerable.Range(0, hexNumber.Length)\n .Where(x => x % 2 == 0)\n .Select(x => Convert.ToByte(hexNumber.Substring(x, 2), 16))\n .ToArray();\n return new BigInteger(bytes.Concat(new byte[] {0}).ToArray());\n }\n public static BigInteger BigIntegerBase10(this string str)\n {\n var number = new BigInteger();\n int i;\n for (i = 0; i < str.Length; i++)\n if (str[i] >= '0' && str[i] <= '9')\n number = number * Ten + long.Parse(str[i].ToString());\n return number;\n }\n private static byte[] HexToByteArray(this string hex)\n {\n return Enumerable.Range(0, hex.Length)\n .Where(x => x % 2 == 0)\n .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))\n .ToArray();\n }\n public static BigInteger ToBigInteger(this char ul)\n {\n return new BigInteger(ul);\n }\n public static BigInteger ToBigInteger(this byte ul)\n {\n return new BigInteger(ul);\n }\n public static BigInteger ToBigInteger(this sbyte ul)\n {\n return new BigInteger(ul);\n }\n public static BigInteger ToBigInteger(this short ul)\n {\n return new BigInteger(ul);\n }\n public static BigInteger ToBigInteger(this ushort ul)\n {\n return new BigInteger(ul);\n }\n public static BigInteger ToBigInteger(this int ul)\n {\n return new BigInteger((ulong) ul);\n }\n public static BigInteger ToBigInteger(this uint ul)\n {\n return new BigInteger((ulong) ul);\n }\n public static BigInteger ToBigInteger(this long ul)\n {\n return new BigInteger((ulong) ul);\n }\n public static BigInteger ToBigInteger(this ulong ul)\n {\n return new BigInteger(ul);\n }\n public static BigInteger ModPow(this BigInteger n, BigInteger e, BigInteger m)\n {\n var s = ONE;\n var u = e;\n while (!u.IsZero)\n {\n if ((u & ONE) == 1)\n s = s * n % m;\n u >>= 1;\n n = n * n % m;\n }\n return s;\n }\n public static double ConfidenceToProbability(int confidence)\n {\n var a = Two.Pow(confidence);\n var b = 100.0 \/ (double) a;\n var c = 100.0 - b;\n return c;\n }\n public static BigInteger Pow(this BigInteger n, BigInteger exp)\n {\n var y = ONE;\n var z = n;\n while (exp != 0)\n {\n if ((exp & 0x1) == 1)\n y *= z;\n exp >>= 1;\n if (exp != 0)\n z *= z;\n }\n return y;\n }\n public static List<BigInteger> GetFactors(this BigInteger n)\n {\n var Factors = new List<BigInteger>();\n var s = n.Sqrt();\n var a = Three;\n while (a < s)\n {\n if (n % a == 0)\n {\n Factors.Add(a);\n if (a * a != n)\n Factors.Add(n \/ a);\n }\n a += 2;\n }\n return Factors;\n }\n public static BigInteger Gcd(this BigInteger a, BigInteger b)\n {\n while (b > BigInteger.Zero)\n {\n var r = a % b;\n a = b;\n b = r;\n }\n return a;\n }\n public static BigInteger Lcm(this BigInteger a, BigInteger b)\n {\n return a * b \/ a.Gcd(b);\n }\n public static BigInteger BigIntegerBase2(this BigInteger bi, string binaryValue)\n {\n bi = BigInteger.Zero;\n if (binaryValue.Count(b => b == '1') + binaryValue.Count(b => b == '0') != binaryValue.Length)\n return bi;\n foreach (var c in binaryValue)\n {\n bi <<= 1;\n bi += c == '1' ? 1 : 0;\n }\n return bi;\n }\n public static int GetByteWidth(this BigInteger n)\n {\n return GetBitWidth(n) >> 3;\n }\n public static int GetBitWidth(this BigInteger n)\n {\n BigInteger bitWidth = 1;\n var v = n;\n while ((v >>= 1) > 0)\n bitWidth++;\n if (bitWidth < 8)\n bitWidth = 8;\n return (int) bitWidth;\n }\n public static BigInteger GetMaxValue(this BigInteger bi, int bitLength)\n {\n if (bi.Sign == -1)\n bitLength -= 1;\n return BigInteger.One << bitLength;\n }\n public static BigInteger GetMaxValue(this BigInteger bi)\n {\n var bitLength = bi.GetBitWidth();\n if (bi.Sign == -1)\n bitLength -= 1;\n return (BigInteger.One << bitLength) - BigInteger.One;\n }\n public static BigInteger GetMaxValueBitWidth(int bitLength)\n {\n return (BigInteger.One << bitLength) - BigInteger.One;\n }\n public static BigInteger BigIntegerBase16(this BigInteger bi, string hexNumber)\n {\n if (string.IsNullOrEmpty(hexNumber))\n throw new Exception(\"Error: hexNumber cannot be either null or have a length of zero.\");\n if (!hexNumber.ContainsOnly(\"0123456789abcdefABCDEFxX\"))\n throw new Exception(\"Error: hexNumber cannot contain characters other than 0-9,a-f,A-F, or xX\");\n hexNumber = hexNumber.ToUpper();\n if (hexNumber.IndexOf(\"0X\", StringComparison.OrdinalIgnoreCase) != -1)\n hexNumber = hexNumber.Substring(2);\n var bytes = Enumerable.Range(0, hexNumber.Length)\n .Where(x => x % 2 == 0)\n .Select(x => Convert.ToByte(hexNumber.Substring(x, 2), 16))\n .ToArray();\n return new BigInteger(bytes.Concat(new byte[] {0}).ToArray());\n }\n public static BigInteger BigIntegerBase10(this BigInteger bi, string str)\n {\n if (str[0] == '-' || str.IndexOf('.') != -1)\n throw new Exception($\"Invalid numeric string. Only positive numbers and whole numbers are allowed. Value={str}\");\n var number = new BigInteger();\n int i;\n for (i = 0; i < str.Length; i++)\n if (str[i] >= '0' && str[i] <= '9')\n number = number * Ten + long.Parse(str[i].ToString());\n return number;\n }\n public static string ToBinaryString(this BigInteger bigint)\n {\n var bytes = bigint.ToByteArray();\n var index = bytes.Length - 1;\n var base2 = new StringBuilder(bytes.Length * 8);\n var binary = Convert.ToString(bytes[index], 2);\n if (binary[0] != '0' && bigint.Sign == 1) base2.Append('0');\n base2.Append(binary);\n for (index--; index >= 0; index--)\n base2.Append(Convert.ToString(bytes[index], 2).PadLeft(8, '0'));\n return base2.ToString();\n }\n public static string ToHexString(this BigInteger bi)\n {\n var bytes = bi.ToByteArray();\n var sb = new StringBuilder();\n foreach (var b in bytes)\n {\n var hex = b.ToString(\"X2\");\n sb.Append(hex);\n }\n return sb.ToString();\n }\n public static string ToOctalString(this BigInteger bigint)\n {\n var bytes = bigint.ToByteArray();\n var index = bytes.Length - 1;\n var base8 = new StringBuilder((bytes.Length \/ 3 + 1) * 8);\n var rem = bytes.Length % 3;\n if (rem == 0) rem = 3;\n var base0 = 0;\n while (rem != 0)\n {\n base0 <<= 8;\n base0 += bytes[index--];\n rem--;\n }\n var octal = Convert.ToString(base0, 8);\n if (octal[0] != '0' && bigint.Sign == 1) base8.Append('0');\n base8.Append(octal);\n while (index >= 0)\n {\n base0 = (bytes[index] << 16) + (bytes[index - 1] << 8) + bytes[index - 2];\n base8.Append(Convert.ToString(base0, 8).PadLeft(8, '0'));\n index -= 3;\n }\n return base8.ToString();\n }\n \/\/\/ <summary>\n \/\/\/ Approximation\n \/\/\/ <\/summary>\n public static BigInteger Sqrt(this BigInteger n)\n {\n var q = BigInteger.One << ((int) BigInteger.Log(n, 2) >> 1);\n var m = BigInteger.Zero;\n while (BigInteger.Abs(q - m) >= 1)\n {\n m = q;\n q = (m + n \/ m) >> 1;\n }\n return q;\n }\n}<\/pre>\n","protected":false},"excerpt":{"rendered":"BigInteger Helper Class<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[2],"tags":[14,29,28],"_links":{"self":[{"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/posts\/266"}],"collection":[{"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/comments?post=266"}],"version-history":[{"count":1,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/posts\/266\/revisions"}],"predecessor-version":[{"id":267,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/posts\/266\/revisions\/267"}],"wp:attachment":[{"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/media?parent=266"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/categories?post=266"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/tags?post=266"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}