public Dag(string inputFile)
{
string[] lines = System.IO.File.ReadAllLines(inputFile);
this.size = lines.Length;
entryMatrix = new int[size][];
for (int i = 0; i < size; i++)
{
entryMatrix[i] = new int[size];
string[] values = lines[i].Split(' ');
for (int j = 0; j < values.Length; j++)
{
entryMatrix[i][j] = Int32.Parse(values[j].Trim());
}
}
maxSumUntilNode = new PathSum[size][];
for (int i = 0; i < size; i++)
{
maxSumUntilNode[i] = new PathSum[size];
for (int j = 0; j < size; j++)
{
maxSumUntilNode[i][j] = null;
}
}
}
static void Main(string[] args)
{
Dag triangle = new Dag("inputs/input2.txt");
PathSum maxSum = triangle.getMaxSum();
Console.WriteLine(maxSum.PrettyString);
}
private PathSum getMaxSumUntilNode(int i, int j)
{
if (i < 0 || j < 0)
{
return(null);
}
if (i == 0)
{
if (j == 0)
{
if (maxSumUntilNode[0][0] == null)
{
maxSumUntilNode[0][0] = new PathSum(entryMatrix[0][0]);
}
return(maxSumUntilNode[0][0]);
}
return(null);
}
if (maxSumUntilNode[i][j] != null)
{
return(maxSumUntilNode[i][j]);
}
if (CanBeUsedInSum(i, j))
{
PathSum max = null;
int maxVal = Int32.MinValue;
PathSum maxUntilParent1 = getMaxSumUntilNode(i - 1, j);
PathSum maxUntilParent2 = getMaxSumUntilNode(i - 1, j - 1);
if (maxUntilParent1 != null && maxUntilParent1.Sum > maxVal)
{
max = maxUntilParent1.Clone();
maxVal = max.Sum;
}
if (maxUntilParent2 != null && maxUntilParent2.Sum > maxVal)
{
max = maxUntilParent2.Clone();
maxVal = max.Sum;
}
if (max != null)
{
max.addValue(entryMatrix[i][j]);
}
return(max);
}
else
{
return(null);
}
}
public PathSum Clone()
{
PathSum result = null;
if (path.Count <= 0)
{
return(result);
}
result = new PathSum(path[0]);
for (int i = 1; i < path.Count; i++)
{
result.addValue(path[i]);
}
return(result);
}
public PathSum getMaxSum()
{
PathSum max = null;
int maxSum = Int32.MinValue;
for (int j = 0; j < size; j++)
{
PathSum currentLeafMax = getMaxSumUntilNode(size - 1, j);
if (currentLeafMax != null && currentLeafMax.Sum > maxSum)
{
max = currentLeafMax;
maxSum = max.Sum;
}
}
return(max);
}
