public void Split()
{
//To split a regular number, replace it with a pair;
//the left element of the pair should be the regular number divided by two and rounded down,
//while the right element of the pair should be the regular number divided by two and rounded up.
//For example, 10 becomes [5,5], 11 becomes [5,6], 12 becomes [6,6], and so on.
var half = Math.DivRem(Number, 2, out int remainder);
Number = half;
var right = new SnailfishRegularNumber(half + remainder);
var currentParent = Parent;
var currenPosition = NumberPosition;
SnailfishNumberPair replacement = new SnailfishNumberPair(this, right);
replacement.Parent = currentParent;
replacement.NumberPosition = currenPosition;
if (currenPosition == PairPosition.Left)
{
currentParent.LeftNumber = replacement;
}
else
{
currentParent.RightNumber = replacement;
}
}
public List <SnailfishNumber> ParseFile(string filePath)
{
var numbers = new List <SnailfishNumber>();
foreach (var line in ReadData(filePath))
{
SnailfishNumberPair currentPair = ParseNumber(line);
numbers.Add(currentPair);
}
return(numbers);
}
public void SingleExplode()
{
//[[[[[9,8],1],2],3],4] => [[[[0,9],2],3],4]
var pair = new SnailfishNumberPair(new SnailfishRegularNumber(9), new SnailfishRegularNumber(8));
var pair2 = new SnailfishNumberPair(pair, new SnailfishRegularNumber(1));
var pair3 = new SnailfishNumberPair(pair2, new SnailfishRegularNumber(2));
var pair4 = new SnailfishNumberPair(pair3, new SnailfishRegularNumber(3));
var pair5 = new SnailfishNumberPair(pair4, new SnailfishRegularNumber(4));
pair5.Reduce();
Assert.AreEqual(true, pair2.LeftNumber is SnailfishRegularNumber);
Assert.AreEqual(true, pair2.RightNumber is SnailfishRegularNumber);
Assert.AreEqual(0, ((SnailfishRegularNumber)pair2.LeftNumber).Number);
Assert.AreEqual(9, ((SnailfishRegularNumber)pair2.RightNumber).Number);
}
public void SingleMagnitude()
{
//[[[[8,7],[7,7]],[[8,6],[7,7]]],[[[0,7],[6,6]],[8,7]]]
// \1/ \2/ \3/ \4/ \5/ \6/ \7/
// ***8*** ***9*** ***10** *
// ******11****** *****12****
// ************13***************
var pair1 = new SnailfishNumberPair(new SnailfishRegularNumber(8), new SnailfishRegularNumber(7));
var pair2 = new SnailfishNumberPair(new SnailfishRegularNumber(7), new SnailfishRegularNumber(7));
var pair3 = new SnailfishNumberPair(new SnailfishRegularNumber(8), new SnailfishRegularNumber(6));
var pair4 = new SnailfishNumberPair(new SnailfishRegularNumber(7), new SnailfishRegularNumber(7));
var pair5 = new SnailfishNumberPair(new SnailfishRegularNumber(0), new SnailfishRegularNumber(7));
var pair6 = new SnailfishNumberPair(new SnailfishRegularNumber(6), new SnailfishRegularNumber(6));
var pair7 = new SnailfishNumberPair(new SnailfishRegularNumber(8), new SnailfishRegularNumber(7));
var pair8 = new SnailfishNumberPair(pair1, pair2);
var pair9 = new SnailfishNumberPair(pair3, pair4);
var pair10 = new SnailfishNumberPair(pair5, pair6);
var pair11 = new SnailfishNumberPair(pair8, pair9);
var pair12 = new SnailfishNumberPair(pair10, pair7);
var pair13 = new SnailfishNumberPair(pair11, pair12);
Assert.AreEqual(3488, pair13.Magnitude);
}
internal static SnailfishNumberPair ParseNumber(string numberString)
{
SnailfishNumberPair currentPair = null;
Stack <SnailfishNumberPair> pairs = new Stack <SnailfishNumberPair>();
foreach (var letter in numberString)
{
switch (letter)
{
case '[':
//add pair
if (currentPair != null)
{
pairs.Push(currentPair);
}
currentPair = new SnailfishNumberPair();
var parent = pairs.Count > 0 ? pairs.Peek() : null;
if (parent != null)
{
currentPair.Parent = parent;
if (parent?.LeftNumber == null)
{
parent.SetLeft(currentPair);
}
else
{
parent.SetRight(currentPair);
}
}
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
var number = new SnailfishRegularNumber(Convert.ToInt32(letter.ToString()));
if (currentPair?.LeftNumber == null)
{
currentPair.SetLeft(number);
}
else
{
currentPair.SetRight(number);
}
break;
case ']':
currentPair = pairs.Count > 0 ? pairs.Pop() : currentPair;
break;
case ',':
//do nothing, logic is in set number
default:
break;
}
}
return(currentPair);
}
