116 lines
4.3 KiB
C#
116 lines
4.3 KiB
C#
using System.Diagnostics.CodeAnalysis;
|
|
|
|
namespace InnovEnergy.Lib.Utils;
|
|
|
|
public static class GraphTraversal
|
|
{
|
|
public static IEnumerable<T> TraverseDepthFirstPreOrder<T>(T root,
|
|
Func<T, IEnumerable<T>> getChildren,
|
|
IEqualityComparer<T>? comparer = null)
|
|
{
|
|
return Traverse(root, TreeTraversal.TraverseDepthFirstPreOrder, getChildren, comparer);
|
|
}
|
|
|
|
|
|
public static IEnumerable<T> TraverseDepthFirstPostOrder<T>(T root,
|
|
Func<T, IEnumerable<T>> getChildren,
|
|
IEqualityComparer<T>? comparer = null)
|
|
{
|
|
return Traverse(root, TreeTraversal.TraverseDepthFirstPostOrder, getChildren, comparer);
|
|
}
|
|
|
|
public static IEnumerable<T> TraverseBreadthFirst<T>(T root,
|
|
Func<T, IEnumerable<T>> getChildren,
|
|
IEqualityComparer<T>? comparer = null)
|
|
{
|
|
return Traverse(root, TreeTraversal.TraverseBreadthFirst, getChildren, comparer);
|
|
}
|
|
|
|
public static IEnumerable<T> TraverseDepthFirstPreOrder<T>(IEnumerable<T> sources,
|
|
Func<T, IEnumerable<T>> getChildren,
|
|
IEqualityComparer<T>? comparer = null)
|
|
{
|
|
return Traverse(sources, TreeTraversal.TraverseDepthFirstPreOrder, getChildren, comparer);
|
|
}
|
|
|
|
|
|
public static IEnumerable<T> TraverseDepthFirstPostOrder<T>(IEnumerable<T> sources,
|
|
Func<T, IEnumerable<T>> getChildren,
|
|
IEqualityComparer<T>? comparer = null)
|
|
{
|
|
return Traverse(sources, TreeTraversal.TraverseDepthFirstPostOrder, getChildren, comparer);
|
|
}
|
|
|
|
public static IEnumerable<T> TraverseBreadthFirst<T>(IEnumerable<T> sources,
|
|
Func<T, IEnumerable<T>> getChildren,
|
|
IEqualityComparer<T>? comparer = null)
|
|
{
|
|
return Traverse(sources, TreeTraversal.TraverseBreadthFirst, getChildren, comparer);
|
|
}
|
|
|
|
|
|
private static IEnumerable<T> Traverse<T>(T root,
|
|
Func<T , Func<T, IEnumerable<T>>,IEnumerable<T>> traversor,
|
|
Func<T, IEnumerable<T>> getChildren,
|
|
IEqualityComparer<T>? comparer = null)
|
|
{
|
|
var getUniqueChildren = GetUniqueChildren(getChildren, root, comparer);
|
|
return traversor(root, getUniqueChildren);
|
|
}
|
|
|
|
[SuppressMessage("ReSharper", "PossibleMultipleEnumeration")]
|
|
private static IEnumerable<T> Traverse<T>(IEnumerable<T> sources,
|
|
Func<T , Func<T, IEnumerable<T>>,IEnumerable<T>> traversor,
|
|
Func<T, IEnumerable<T>> getChildren,
|
|
IEqualityComparer<T>? comparer = null)
|
|
{
|
|
var set = new HashSet<T>(sources, comparer ?? EqualityComparer<T>.Default);
|
|
IEnumerable<T> GetUniqueChildren(T n) => getChildren(n).Where(set.Add);
|
|
|
|
return from s in sources
|
|
from e in traversor(s, GetUniqueChildren)
|
|
select e;
|
|
}
|
|
|
|
// TODO: IEqualityComparer
|
|
public static IEnumerable<(T source, T target)> Edges<T>(T node, Func<T, IEnumerable<T>> getChildren)
|
|
{
|
|
return Edges(node.AsSingleEnumerable(), getChildren);
|
|
}
|
|
|
|
|
|
// TODO: IEqualityComparer
|
|
public static IEnumerable<(T source, T target)> Edges<T>(IEnumerable<T> sources,
|
|
Func<T, IEnumerable<T>> getChildren)
|
|
{
|
|
var hs = new HashSet<(T source, T target)>();
|
|
|
|
IEnumerable<(T source, T target)> GetChildEdges((T source, T target) edge)
|
|
{
|
|
return getChildren(edge.target)
|
|
.Select(c => (edge.target, c))
|
|
.Where(hs!.Add);
|
|
}
|
|
|
|
return from src in sources.Select(s => (s, s))
|
|
from e in TreeTraversal.TraverseDepthFirstPreOrder(src, GetChildEdges).Skip(1)
|
|
select e;
|
|
}
|
|
|
|
private static Func<T, IEnumerable<T>> GetUniqueChildren<T>(Func<T, IEnumerable<T>> getChildren,
|
|
T root,
|
|
IEqualityComparer<T>? comparer)
|
|
{
|
|
return GetUniqueChildren(getChildren, root.AsSingleEnumerable(), comparer);
|
|
}
|
|
|
|
private static Func<T, IEnumerable<T>> GetUniqueChildren<T>(Func<T, IEnumerable<T>> getChildren,
|
|
IEnumerable<T> sources,
|
|
IEqualityComparer<T>? comparer)
|
|
{
|
|
var set = new HashSet<T>(sources, comparer ?? EqualityComparer<T>.Default);
|
|
return n => getChildren(n).Where(set.Add);
|
|
}
|
|
|
|
|
|
} |