public string FindLcs(string x, string y)
{
var context = new LcsSearchContext();
context.X = x;
context.Y = y;
context.Output = new StringBuilder();
context.LcsLengthsTable = BuildLcsLengthsTable(x, y);
FindLcs(context, x.Length, y.Length);
return(context.Output.ToString());
}
private void FindLcs(LcsSearchContext context, int lengthOfX, int lengthOfY)
{
if (lengthOfX == 0 || lengthOfY == 0)
{
return;
}
if (context.LcsLengthsTable[lengthOfX, lengthOfY].Direction == SearchDirection.Diagonal)
{
FindLcs(context, lengthOfX - 1, lengthOfY - 1);
context.Output.Append(context.X[lengthOfX - 1]);
}
else if (context.LcsLengthsTable[lengthOfX, lengthOfY].Direction == SearchDirection.Up)
{
FindLcs(context, lengthOfX - 1, lengthOfY);
}
else
{
FindLcs(context, lengthOfX, lengthOfY - 1);
}
}
