public MyNumberItem(MyNumberItem left, MyNumberItem right, int numbersUsed,
int currentValue, MyNumberOperators operand, int mask, int startIndex)
{
this.left = left;
this.right = right;
this.currentValue = currentValue;
this.operand = operand;
this.mask = mask;
this.numbersUsed = numbersUsed;
this.startIndex = startIndex;
}
public MyNumberItem CalculateNew(MyNumberItem right, MyNumberOperators op, int newStartIndex)
{
int newValue;
switch (op)
{
case MyNumberOperators.ADD:
newValue = this.currentValue + right.currentValue;
break;
case MyNumberOperators.SUB:
newValue = this.currentValue - right.currentValue;
if (newValue <= 0) // x - (y - z) is same as x + (z - y) and zero does not make any sense
{
return(null);
}
break;
case MyNumberOperators.MULTIPLY:
newValue = this.currentValue * right.currentValue;
break;
case MyNumberOperators.DIVIDE:
if (right.currentValue == 0)
{
return(null);
}
newValue = currentValue / right.currentValue;
// not fully dividable
if (newValue * right.currentValue != currentValue)
{
return(null);
}
break;
default:
return(null);
}
MyNumberItem item = new MyNumberItem(this, right, numbersUsed + right.numbersUsed,
newValue, op, mask | right.mask, newStartIndex);
return(item);
}
