public void Append(eeObject obj)
{
_count += eeNumber.ONE;
if (LastNode == null) // if this is the second object to enter the list
{
var node = new eeListNode(obj.Copy(), _count.Copy(), HeadNode, null);
LastNode = node;
HeadNode.next = node;
return;
}
var newNode = new eeListNode(obj.Copy(), _count.Copy(), LastNode, null);
this.LastNode.next = newNode;
this.LastNode = newNode;
}
// Greatest Common Factor using Euclid's algorithm
public eeNumber GCF(eeNumber prod2_orig)
{
var prod1 = this.Copy().AbsoluteValue();
var prod2 = prod2_orig.Copy().AbsoluteValue();
while (prod1 != ZERO && prod2 != ZERO)
{
if (prod1 > prod2)
{
prod1 %= prod2;
}
else
{
prod2 %= prod1;
}
}
return(prod1 | prod2);
}
// Warning: Subtraction will destroy the contents of num2 and set the contents of num1 to the result
// Make sure to pass a copy of num2 if you are keeping its value
public static eeNumber operator -(eeNumber num1_orig, eeNumber num2_orig)
{
eeNumber num1 = num1_orig.Copy(),
num2 = num2_orig.Copy();
// If either number is a fraction, cross multiply
if (num1.IsFrac() || num2.IsFrac())
{
eeNumber frac1 = num1.PopDenominator(),
frac2 = num2.PopDenominator();
num1 *= frac2;
num2 *= frac1;
var ret = (num1 - num2) / (frac1 * frac2);
ret.TrimZeros();
ret.Simplify();
return(ret);
}
// if the two nums are the same
if (num1 == num2)
{
return(ZERO.Copy());
}
// if first num is negative
else if (num1.negative && !num2.negative)
{
// add them then negate it
num1.negative = false;
var sum = num1 + num2;
sum.negative = true;
return(sum);
}
// if second num is negative
else if (num2.negative && !num1.negative)
{
// minus and negatives cancel
num2.negative = false;
return(num1 + num2);
}
// If they're both negative
else if (num1.negative && num2.negative)
{
// Treat this as adding a negative to a positive
num2.negative = false;
return(num1 + num2);
}
// If we're going to get a negative answer
bool negate = false;
if (num2 > num1)
{
// reverse the two
var buf = num1;
num1 = num2;
num2 = buf;
// and negate
negate = true;
}
// Reverse because we're subtracting from right to left.
byte[] l_bytes = num1.bytes.Reverse().ToArray(),
r_bytes = num2.bytes.Reverse().ToArray();
bool carry = false;
int i;
for (i = 0; i < r_bytes.Length; i++)
{
// Account for the previous carry
if (carry)
{
r_bytes[i]++;
carry = false;
}
// Subtract the digits
byte digitDiff;
if (l_bytes[i] < r_bytes[i]) // account for carry
{
digitDiff = (byte)((10 + l_bytes[i]) - r_bytes[i]);
carry = true;
}
else
{
digitDiff = (byte)(l_bytes[i] - r_bytes[i]);
}
// Set the digit
l_bytes[i] = digitDiff;
}
// If there is still carry left
while (carry)
{
// subtract one from the next value
if (l_bytes[i] == 0)
{
l_bytes[i] = 9;
i++;
}
else
{
l_bytes[i] -= 1;
carry = false;
}
}
// Put it in order again
l_bytes = l_bytes.Reverse().ToArray();
num1.bytes = l_bytes;
num1.negative = negate;
num1.TrimZeros();
return(num1);
}
