private static ISet <ITreeProgram <TOutput> > GetSubCombs <TOutput>(ITreeProgram <TOutput> program)
{
var combs = new HashSet <ITreeProgram <TOutput> >();
if (program == null)
{
return(combs);
}
// checks no more children
if (program.IsLeaf())
{
combs.Add(program);
return(combs);
}
// gets sub-programs from all children
var childrenSubCombs = new List <IEnumerable <ITreeProgram <TOutput> > >();
foreach (var child in program.Input)
{
var childSubCombs = GetSubCombs(child);
childrenSubCombs.Add(childSubCombs);
// adds the sub-combinations of children to combination list
foreach (var childSubComb in childSubCombs)
{
combs.Add(childSubComb);
}
}
// creates new programs where each child is replaced by some sub-combination of it
var allChildrenCombs = childrenSubCombs.GetAllCombinations();
foreach (var children in allChildrenCombs)
{
if (children.Count == program.Input.Count)
{
combs.Add(program.CreateNew(children));
}
}
childrenSubCombs.Clear();
return(combs);
}