private AlgebExpression LookAndAddValue(AlgebVal val)
{
if (val.Coaf == 0)
return this;
if (this.op == Operation.Value)
return this + val;
if (this.op == Operation.Addition)
{
if (this.right.value.Value.Coaf == 0)
return left.LookAndAddValue(val);
else if (this.right.value.Value.Pow == val.Pow)
return left + (right.value.Value + val);
else
return left.LookAndAddValue(val) + right;
}
else
throw new InvalidOperationException("can only be done on addition trees");
}
public AlgebExpression(AlgebVal val)
{
op = Operation.Value;
value = val;
}
public static bool TryParse(string s, out AlgebVal av)
{
Regex avreg = new Regex(@"^\-?[0-9\.]*x?\^?[0-9]*$");
if (avreg.IsMatch(s))
{
if (!s.Contains('x'))
s = s + "x^0";
if (s.EndsWith("x"))
s = s + "^1";
if (s.StartsWith("x"))
s = "1" + s;
av = Parse(s);
return true;
}
av = new AlgebVal(0, 0);
return false;
}