private bool IsQuadResModProduct( uint Prime )
{
// Euler's Criterion:
Integer Exponent = new Integer();
Integer Result = new Integer();
Integer Modulus = new Integer();
Exponent.SetFromULong( Prime );
IntMath.SubtractULong( Exponent, 1 );
Exponent.ShiftRight( 1 ); // Divide by 2.
Result.Copy( Product );
Modulus.SetFromULong( Prime );
IntMath.IntMathNew.ModularPower( Result, Exponent, Modulus, false );
if( Result.IsOne() )
return true;
else
return false; // Result should be Prime - 1.
}
// Factor 2 is along the right side diagonal.
internal void SetFactor2( Integer UseBigIntToSet )
{
Integer BigIntToSet = new Integer();
BigIntToSet.Copy( UseBigIntToSet );
if( (BigIntToSet.GetD( 0 ) & 1 ) != 1 )
throw( new Exception( "Factor2 can't be even." ));
uint ToSet = MultArray[0].OneLine[0];
ToSet = SetMult1( ToSet );
ToSet = SetMult2( ToSet );
ToSet = SetMult( ToSet );
ToSet = SetAccumOut( ToSet );
ToSet = ClearCarryOut( ToSet );
MultArray[0].OneLine[0] = ToSet;
// Factor2 has to be odd so Mult2 is set to
// 1 all the way across the top.
SetMult2AtRow( 0 );
BigIntToSet.ShiftRight( 1 );
if( BigIntToSet.IsZero())
throw( new Exception( "Factor2 can't be 1." ));
// 107 = 64 + 32 + 8 + 2 + 1
int Where = 1;
for( int Row = 1; Row < MultArraySize; Row++ )
{
ToSet = MultArray[Row].OneLine[0];
if( (BigIntToSet.GetD( 0 ) & 1 ) == 1 )
ToSet = SetMult2( ToSet );
else
ToSet = ClearMult2( ToSet );
MultArray[Row].OneLine[0] = ToSet;
Where = Row;
BigIntToSet.ShiftRight( 1 );
if( BigIntToSet.IsZero())
break;
}
// At the last 1 bit.
// ToSet = MultArray[Where].OneLine[0];
for( int Row = Where + 1; Row < MultArraySize; Row++ )
{
ToSet = MultArray[Row].OneLine[0];
ToSet = ClearMult2( ToSet );
MultArray[Row].OneLine[0] = ToSet;
}
}
// Product is along the right side diagonal.
internal void SetProduct( Integer UseBigIntToSet )
{
Integer BigIntToSet = new Integer();
BigIntToSet.Copy( UseBigIntToSet );
// Primes: 29, 31, 37, 41, 43, 47, 53, 59, 61, 67,
// 71, 73, 79, 83, 89, 97, 101, 103, 107
if( (BigIntToSet.GetD( 0 ) & 1 ) != 1 )
throw( new Exception( "Product can't be even." ));
int Where = 0;
uint ToSet = 0;
for( int Row = 0; Row < MultArraySize; Row++ )
{
ToSet = MultArray[Row].OneLine[0];
if( (BigIntToSet.GetD( 0 ) & 1 ) == 1 )
ToSet = SetAccumOut( ToSet );
else
ToSet = ClearAccumOut( ToSet );
MultArray[Row].OneLine[0] = ToSet;
Where = Row;
BigIntToSet.ShiftRight( 1 );
if( BigIntToSet.IsZero())
break;
}
ProductBitIndex = Where;
int HowMany = ProductBitIndex + 1;
MForm.ShowStatus( "There were " + HowMany.ToString() + " bits in the product." );
// At the last 1 bit.
ToSet = MultArray[Where].OneLine[0];
ToSet = ClearCarryOut( ToSet );
MultArray[Where].OneLine[0] = ToSet;
// The ProductBits can be:
// Factor1Bits + Factor2Bits
// or it can be:
// Factor1Bits + Factor2Bits + 1
// ProductBits - Factor1Bits = Factor2Bits ( + 1 or not)
int Factor1Bits = GetHighestMult1BitIndex() + 1;
int ProductBits = (Where + 1);
// Factor2Bits might be this or it might be one
// less than this.
int MaximumFactor2Bits = ProductBits - Factor1Bits;
// Factor2BitIndex = Factor2Bits - 1;
// Test if the top bit of Factor2 is in the right place.
// ToSet = MultArray[Factor2BitIndex].OneLine[0];
// ToSet = SetMult( ToSet );
// MultArray[Factor2BitIndex].OneLine[0] = ToSet;
for( int Row = MaximumFactor2Bits + 1; Row < MultArraySize; Row++ )
{
ToSet = MultArray[Row].OneLine[0];
ToSet = ClearMult2( ToSet );
MultArray[Row].OneLine[0] = ToSet;
}
for( int Row = Where + 1; Row < MultArraySize; Row++ )
{
ToSet = MultArray[Row].OneLine[0];
ToSet = ClearMult2( ToSet );
ToSet = ClearMult( ToSet );
ToSet = ClearAccumOut( ToSet );
ToSet = ClearCarryOut( ToSet );
MultArray[Row].OneLine[0] = ToSet;
}
}
// Factor1 is along the top.
internal void SetFactor1( Integer UseBigIntToSet )
{
Integer BigIntToSet = new Integer();
BigIntToSet.Copy( UseBigIntToSet );
if( (BigIntToSet.GetD( 0 ) & 1 ) != 1 )
throw( new Exception( "Factor1 can't be even." ));
uint ToSet = MultArray[0].OneLine[0];
ToSet = SetMult1( ToSet );
ToSet = SetMult2( ToSet );
ToSet = SetMult( ToSet );
ToSet = SetAccumOut( ToSet );
ToSet = ClearCarryOut( ToSet );
MultArray[0].OneLine[0] = ToSet;
// Factor1 has to be odd so Mult1 is set to
// 1 all the way down the side.
SetMult1AtColumn( 0 );
BigIntToSet.ShiftRight( 1 );
if( BigIntToSet.IsZero())
throw( new Exception( "Factor1 can't be 1." ));
// 107 = 64 + 32 + 8 + 2 + 1
int Where = 1;
for( int Column = 1; Column < MultArraySize; Column++ )
{
ToSet = MultArray[0].OneLine[Column];
if( (BigIntToSet.GetD( 0 ) & 1 ) == 1 )
ToSet = SetMult1( ToSet );
else
ToSet = ClearMult1( ToSet );
MultArray[0].OneLine[Column] = ToSet;
Where = Column;
BigIntToSet.ShiftRight( 1 );
if( BigIntToSet.IsZero())
break;
}
// At the last 1 bit.
// ToSet = MultArray[0].OneLine[Where];
for( int Column = Where + 1; Column < MultArraySize; Column++ )
{
ToSet = MultArray[0].OneLine[Column];
ToSet = ClearMult1( ToSet );
ToSet = ClearMult( ToSet );
ToSet = ClearAccumOut( ToSet );
ToSet = ClearCarryOut( ToSet );
MultArray[0].OneLine[Column] = ToSet;
}
}