// Finished
private static void MultiByteDivide(BigNumber bn1, BigNumber bn2, BigNumber outQuotient,
BigNumber outRemainder)
{
var result = new uint[MaxLength];
var remainderLen = bn1.DataLength + 1;
var remainder = new uint[remainderLen];
var mask = 0x80000000;
var val = bn2.data[bn2.DataLength - 1];
var shift = 0;
var resultPos = 0;
while (mask != 0 && (val & mask) == 0)
{
++shift;
mask >>= 1;
}
for (var i = 0; i < bn1.DataLength; ++i)
{
remainder[i] = bn1.data[i];
}
ShiftLeft(remainder, shift);
bn2 = bn2 << shift;
var j = remainderLen - bn2.DataLength;
var pos = remainderLen - 1;
ulong firstDivisorByte = bn2.data[bn2.DataLength - 1];
ulong secondDivisorByte = bn2.data[bn2.DataLength - 2];
var divisorLen = bn2.DataLength + 1;
var dividendPart = new uint[divisorLen];
while (j > 0)
{
var dividend = ((ulong)remainder[pos] << 32) + remainder[pos - 1];
var qHat = dividend / firstDivisorByte;
var rHat = dividend % firstDivisorByte;
var done = false;
while (!done)
{
done = true;
if (qHat == 0x100000000 || qHat * secondDivisorByte > (rHat << 32) + remainder[pos - 2])
{
--qHat;
rHat += firstDivisorByte;
if (rHat < 0x100000000)
{
done = false;
}
}
}
for (var h = 0; h < divisorLen; ++h)
{
dividendPart[h] = remainder[pos - h];
}
var kk = new BigNumber(dividendPart);
var ss = bn2 * (long)qHat;
while (ss > kk)
{
--qHat;
ss -= bn2;
}
var yy = kk - ss;
for (var h = 0; h < divisorLen; ++h)
{
remainder[pos - h] = yy.data[bn2.DataLength - h];
}
result[resultPos++] = (uint)qHat;
--pos;
--j;
}
outQuotient.DataLength = resultPos;
var y = 0;
for (var x = outQuotient.DataLength - 1; x >= 0; --x, ++y)
{
outQuotient.data[y] = result[x];
}
for (; y < MaxLength; ++y)
{
outQuotient.data[y] = 0;
}
while (outQuotient.DataLength > 1 && outQuotient.data[outQuotient.DataLength - 1] == 0)
{
--outQuotient.DataLength;
}
if (outQuotient.DataLength == 0)
{
outQuotient.DataLength = 1;
}
outRemainder.DataLength = ShiftRight(remainder, shift);
for (y = 0; y < outRemainder.DataLength; ++y)
{
outRemainder.data[y] = remainder[y];
}
for (; y < MaxLength; ++y)
{
outRemainder.data[y] = 0;
}
}
// Finished
private static void SingleByteDivide(BigNumber bn1, BigNumber bn2, BigNumber outQuotient,
BigNumber outRemainder)
{
var result = new uint[MaxLength];
var resultPos = 0;
for (var i = 0; i < MaxLength; ++i)
{
outRemainder.data[i] = bn1.data[i];
}
outRemainder.DataLength = bn1.DataLength;
while (outRemainder.DataLength > 1 && outRemainder.data[outRemainder.DataLength - 1] == 0)
{
--outRemainder.DataLength;
}
ulong divisor = bn2.data[0];
var pos = outRemainder.DataLength - 1;
ulong dividend = outRemainder.data[pos];
if (dividend >= divisor)
{
var quotient = dividend / divisor;
result[resultPos++] = (uint)quotient;
outRemainder.data[pos] = (uint)(dividend % divisor);
}
--pos;
while (pos >= 0)
{
dividend = ((ulong)outRemainder.data[pos + 1] << 32) + outRemainder.data[pos];
var quotient = dividend / divisor;
result[resultPos++] = (uint)quotient;
outRemainder.data[pos + 1] = 0;
outRemainder.data[pos--] = (uint)(dividend % divisor);
}
outQuotient.DataLength = resultPos;
var j = 0;
for (var i = outQuotient.DataLength - 1; i >= 0; --i, ++j)
{
outQuotient.data[j] = result[i];
}
for (; j < MaxLength; ++j)
{
outQuotient.data[j] = 0;
}
while (outQuotient.DataLength > 1 && outQuotient.data[outQuotient.DataLength - 1] == 0)
{
--outQuotient.DataLength;
}
if (outQuotient.DataLength == 0)
{
outQuotient.DataLength = 1;
}
while (outRemainder.DataLength > 1 && outRemainder.data[outRemainder.DataLength - 1] == 0)
{
--outRemainder.DataLength;
}
}
// Approved
public BigNumber(string value, int radix)
{
var multiplier = new BigNumber(1);
var result = new BigNumber();
value = value.ToUpper().Trim();
var limit = 0;
if (value[0] == '-')
{
limit = 1;
}
for (var i = value.Length - 1; i >= limit; --i)
{
int posVal = value[i];
if (posVal >= '0' && posVal <= '9')
{
posVal -= '0';
}
else if (posVal >= 'A' && posVal <= 'Z')
{
posVal = posVal - 'A' + 10;
}
else
{
posVal = 9999999;
}
if (posVal >= radix)
{
throw new ArithmeticException($"Invalid string when constructing {nameof(BigNumber)} ({value})");
}
if (value[0] == '-')
{
posVal = -posVal;
}
result = result + multiplier * posVal;
if (i - 1 >= limit)
{
multiplier = multiplier * radix;
}
}
if (value[0] == '-')
{
if ((result.data[MaxLength - 1] & 0x80000000) == 0)
{
throw new ArithmeticException($"Negative underflow while constructing {nameof(BigNumber)}");
}
}
else
{
if ((result.data[MaxLength - 1] & 0x80000000) != 0)
{
throw new ArithmeticException($"Positive overflow while constructing {nameof(BigNumber)}");
}
}
data = new uint[MaxLength];
for (var i = 0; i < result.DataLength; ++i)
{
data[i] = result.data[i];
}
DataLength = result.DataLength;
}
// Approved
public static BigNumber operator *(BigNumber bn1, BigNumber bn2)
{
var lastPos = MaxLength - 1;
var bn1IsNegative = false;
var bn2IsNegative = false;
try
{
if ((bn1.data[lastPos] & 0x80000000) != 0)
{
bn1IsNegative = true;
bn1 = -bn1;
}
if ((bn2.data[lastPos] & 0x80000000) != 0)
{
bn2IsNegative = true;
bn2 = -bn2;
}
}
catch
{
// ignored
}
var result = new BigNumber();
try
{
for (var i = 0; i < bn1.DataLength; ++i)
{
if (bn1.data[i] == 0)
{
continue;
}
ulong mcarry = 0;
for (int j = 0, k = i; j < bn2.DataLength; ++j, ++k)
{
ulong bn1Data = bn1.data[i];
ulong bn2Data = bn2.data[j];
var val = bn1Data * bn2Data + result.data[k] + mcarry;
result.data[k] = (uint)(val & 0xffffffff);
mcarry = val >> 32;
}
if (mcarry != 0)
{
result.data[i + bn2.DataLength] = (uint)mcarry;
}
}
}
catch
{
throw new ArithmeticException("Multiplication overflow");
}
result.DataLength = bn1.DataLength + bn2.DataLength;
if (result.DataLength > MaxLength)
{
result.DataLength = MaxLength;
}
while (result.DataLength > 1 && result.data[result.DataLength - 1] == 0)
{
--result.DataLength;
}
if ((result.data[lastPos] & 0x80000000) != 0)
{
// ReSharper disable once InvertIf
if (bn1IsNegative != bn2IsNegative && result.data[lastPos] == 0x80000000)
{
if (result.DataLength == 1)
{
return(result);
}
var isMaxNegative = true;
for (var i = 0; i < result.DataLength - 1 && isMaxNegative; ++i)
{
if (result.data[i] != 0)
{
isMaxNegative = false;
}
}
if (isMaxNegative)
{
return(result);
}
}
throw new ArithmeticException("Multiplication overflow");
}
if (bn1IsNegative != bn2IsNegative)
{
return(-result);
}
return(result);
}
// Approved
public BigNumber(BigNumber bn)
{
SetValue(bn);
}
// Finished
private static BigNumber BarrettReduction(BigNumber x, BigNumber n, BigNumber constant)
{
var k = n.DataLength;
var kPlusOne = k + 1;
var kMinusOne = k - 1;
var q1 = new BigNumber();
for (int i = kMinusOne, j = 0; i < x.DataLength; ++i, ++j)
{
q1.data[j] = x.data[i];
}
q1.DataLength = x.DataLength - kMinusOne;
if (q1.DataLength <= 0)
{
q1.DataLength = 1;
}
var q2 = q1 * constant;
var q3 = new BigNumber();
for (int i = kPlusOne, j = 0; i < q2.DataLength; ++i, ++j)
{
q3.data[j] = q2.data[i];
}
q3.DataLength = q2.DataLength - kPlusOne;
if (q3.DataLength <= 0)
{
q3.DataLength = 1;
}
//Approved to here
var r1 = new BigNumber();
var lengthToCopy = x.DataLength > kPlusOne ? kPlusOne : x.DataLength;
for (var i = 0; i < lengthToCopy; ++i)
{
r1.data[i] = x.data[i];
}
r1.DataLength = lengthToCopy;
var r2 = new BigNumber();
for (var i = 0; i < q3.DataLength; ++i)
{
if (q3.data[i] == 0)
{
continue;
}
ulong mcarry = 0;
var t = i;
for (var j = 0; j < n.DataLength && t < kPlusOne; ++j, ++t)
{
ulong q3Data = q3.data[i];
ulong nData = n.data[j];
var val = q3Data * nData + r2.data[t] + mcarry;
r2.data[t] = (uint)(val & 0xffffffff);
mcarry = val >> 32;
}
if (t < kPlusOne)
{
r2.data[t] = (uint)mcarry;
}
}
r2.DataLength = kPlusOne;
while (r2.DataLength > 1 && r2.data[r2.DataLength - 1] == 0)
{
--r2.DataLength;
}
r1 -= r2;
if ((r1.data[MaxLength - 1] & 0x80000000) != 0)
{
var val = new BigNumber();
val.data[kPlusOne] = 0x1;
val.DataLength = kPlusOne + 1;
r1 += val;
}
while (r1 >= n)
{
r1 -= n;
}
return(r1);
}
// Finished
public BigNumber ModPow(BigNumber exp, BigNumber n)
{
if ((exp.data[MaxLength - 1] & 0x80000000) != 0)
{
throw new ArithmeticException("Positive exponents only");
}
var resultNum = (BigNumber)1;
BigNumber tempNum;
var thisNegative = false;
if ((data[MaxLength - 1] & 0x80000000) != 0)
{
tempNum = -this % n;
thisNegative = true;
}
else
{
tempNum = this % n;
}
var constant = new BigNumber();
var i = n.DataLength << 1;
constant.data[i] = 0x00000001;
constant.DataLength = i + 1;
constant = constant / n;
var totalBits = exp.BitCount();
var count = 0;
for (var pos = 0; pos < exp.DataLength; ++pos)
{
uint mask = 0x1;
for (var index = 0; index < 32; ++index)
{
if ((exp.data[pos] & mask) != 0)
{
resultNum = BarrettReduction(resultNum * tempNum, n, constant);
}
mask <<= 1;
tempNum = BarrettReduction(tempNum * tempNum, n, constant);
if (tempNum.DataLength == 1 && tempNum.data[0] == 1)
{
if (thisNegative && (exp.data[0] & 0x1) != 0)
{
return(-resultNum);
}
return(resultNum);
}
++count;
if (count == totalBits)
{
break;
}
}
}
if (thisNegative && (exp.data[0] & 0x1) != 0)
{
return(-resultNum);
}
return(resultNum);
}
