c# tree traversal: fixed index out of range issue (#894)

Author: henrikac

contents/tree_traversal/code/csharp/Program.cs

@@ -1,4 +1,3 @@
-// submitted by Julian Schacher (jspp)
 using System;
 
 namespace TreeTraversal

contents/tree_traversal/code/csharp/Tree.cs

@@ -1,4 +1,3 @@
-// submitted by Julian Schacher (jspp)
 using System;
 using System.Collections.Generic;
 
@@ -11,23 +10,23 @@ public class Tree
 
         public Tree(int depthCount, int childrenCount)
         {
-            this.Id = depthCount;
+            Id = 1;
 
             if (depthCount > 0)
             {
                 for (int i = 0; i < childrenCount; i++)
-                    this._children.Add(new Tree(depthCount - 1, childrenCount));
+                    _children.Add(new Tree(Id * 10 + i + 1, depthCount - 1, childrenCount));
             }
         }
 
         private Tree(int id, int depthCount, int childrenCount)
         {
-            this.Id = id;
+            Id = id;
 
             if (!(depthCount <= 1))
             {
                 for (int i = 0; i < childrenCount; i++)
-                    this._children.Add(new Tree(this.Id * 10 + i + 1, depthCount - 1, childrenCount));
+                    _children.Add(new Tree(Id * 10 + i + 1, depthCount - 1, childrenCount));
             }
         }
 
@@ -61,20 +60,25 @@ public void DFSRecursiveInorderBinary()
         {
             DFSRecursiveInorderBinary(this);
 
-            // This assumes only 2 children
             void DFSRecursiveInorderBinary(Tree tree)
             {
-                if (tree._children.Count > 2)
-                    throw new Exception("Not binary tree!");
-
-                if (tree._children.Count > 0)
+                switch (tree._children.Count)
                 {
-                    DFSRecursiveInorderBinary(tree._children[0]);
-                    Console.Write(tree.Id + " ");
-                    DFSRecursiveInorderBinary(tree._children[1]);
+                    case 2:
+                        DFSRecursiveInorderBinary(tree._children[0]);
+                        Console.Write(tree.Id + " ");
+                        DFSRecursiveInorderBinary(tree._children[1]);
+                        break;
+                    case 1:
+                        DFSRecursiveInorderBinary(tree._children[0]);
+                        Console.Write(tree.Id + " ");
+                        break;
+                    case 0:
+                        Console.Write(tree.Id + " ");
+                        break;
+                    default:
+                        throw new Exception("Not binary tree!");
                 }
-                else
-                    Console.Write(tree.Id + " ");
             }
         }
 

contents/tree_traversal/tree_traversal.md

@@ -8,7 +8,7 @@ Trees are naturally recursive data structures, and because of this, we cannot ac
 {% sample lang="cpp" %}
 [import:12-15, lang:"cpp"](code/c++/tree_example.cpp)
 {% sample lang="cs" %}
-[import:7-11, lang:"csharp"](code/csharp/Tree.cs)
+[import:6-10, lang:"csharp"](code/csharp/Tree.cs)
 {% sample lang="c" %}
 [import:7-11, lang:"c"](code/c/tree_traversal.c)
 {% sample lang="java" %}
@@ -56,7 +56,7 @@ Because of this, the most straightforward way to traverse the tree might be recu
 {% sample lang="cpp" %}
 [import:17-24, lang:"cpp"](code/c++/tree_example.cpp)
 {% sample lang="cs" %}
-[import:34-45, lang:"csharp"](code/csharp/Tree.cs)
+[import:33-44, lang:"csharp"](code/csharp/Tree.cs)
 {% sample lang="c" %}
 [import:37-45, lang:"c"](code/c/tree_traversal.c)
 {% sample lang="java" %}
@@ -112,7 +112,7 @@ Now, in this case the first element searched through is still the root of the tr
 {% sample lang="cpp" %}
 [import:26-31, lang:"cpp"](code/c++/tree_example.cpp)
 {% sample lang="cs" %}
-[import:47-58, lang:"csharp"](code/csharp/Tree.cs)
+[import:46-57, lang:"csharp"](code/csharp/Tree.cs)
 {% sample lang="c" %}
 [import:47-53, lang:"c"](code/c/tree_traversal.c)
 {% sample lang="java" %}
@@ -163,7 +163,7 @@ In this case, the first node visited is at the bottom of the tree and moves up t
 {% sample lang="cpp" %}
 [import:34-52 lang:"cpp"](code/c++/tree_example.cpp)
 {% sample lang="cs" %}
-[import:60-79, lang:"csharp"](code/csharp/Tree.cs)
+[import:59-83, lang:"csharp"](code/csharp/Tree.cs)
 {% sample lang="c" %}
 [import:55-73, lang:"c"](code/c/tree_traversal.c)
 {% sample lang="java" %}
@@ -223,7 +223,7 @@ In code, it looks like this:
 {% sample lang="cpp" %}
 [import:55-70, lang:"cpp"](code/c++/tree_example.cpp)
 {% sample lang="cs" %}
-[import:81-94, lang:"csharp"](code/csharp/Tree.cs)
+[import:85-98, lang:"csharp"](code/csharp/Tree.cs)
 {% sample lang="c" %}
 [import:75-93, lang:"c"](code/c/tree_traversal.c)
 {% sample lang="java" %}
@@ -276,7 +276,7 @@ And this is exactly what Breadth-First Search (BFS) does! On top of that, it can
 {% sample lang="cpp" %}
 [import:73-86, lang:"cpp"](code/c++/tree_example.cpp)
 {% sample lang="cs" %}
-[import:96-109, lang:"csharp"](code/csharp/Tree.cs)
+[import:100-113, lang:"csharp"](code/csharp/Tree.cs)
 {% sample lang="c" %}
 [import:95-113, lang:"c"](code/c/tree_traversal.c)
 {% sample lang="java" %}