Working on diagrams for binary trees.

Author: Clément

source/Makefile

@@ -80,6 +80,8 @@ DIAG_DIR = diag/
 CLA_DIR = $(DIAG_DIR)cla/
 # The folder where the flowcharts diagrams are located
 FLO_DIR = $(DIAG_DIR)flo/
+# The folder where the graph diagrams are located
+GRA_DIR = $(DIAG_DIR)gra/
 # The folder where the videos are located.
 VID_DIR = vid/
 # The folders where the project are located.
@@ -374,6 +376,25 @@ $(FLO_DIR)%.png: $(FLO_DIR)%.txt
 	&& mmdc -s 2 -p .puppeteer.json -i  $@_tmp -o $@ \
 	&& rm $@_tmp
 
+# Graph diagram are only used for 
+# binary trees.
+$(GRA_DIR)%.md: $(GRA_DIR)%.txt | $(GRA_DIR)%.svg $(GRA_DIR)%.png
+	echo "![A binary tree diagram ([text version](./$(basename $@).txt), [image version](./$(basename $@).png), [svg version](./$(basename $@).svg))]($(notdir $(basename $@)).png)" > $@
+
+$(GRA_DIR)%.svg: $(GRA_DIR)%.txt
+	@echo "Creating $@"
+	echo "graph TB" > $@_tmp \
+	&& cat $< >> $@_tmp \
+	&& mmdc -p .puppeteer.json -i $@_tmp -o $@ \
+	&& rm $@_tmp
+
+$(GRA_DIR)%.png: $(GRA_DIR)%.txt
+	@echo "Creating $@"
+	echo "graph TB" > $@_tmp \
+	&& cat $< >> $@_tmp \
+	&& mmdc -s 2 -p .puppeteer.json -i  $@_tmp -o $@ \
+	&& rm $@_tmp
+
 # Exercise without solution
 $(EXO_DIR)%.md: $(SOL_DIR)%.md
 	@echo "Creating $@"

source/code/projects/AList/AList/AList.cs

@@ -25,7 +25,16 @@ public bool IsEmpty()
 
   public void Clear()
   {
-    alist = new T[0];
+    if (isReadonly)
+    {
+      throw new InvalidOperationException(
+        "List is read-only, you cannot clear it."
+      );
+    }
+    else
+    {
+      alist = new T[0];
+    }
   }
 
   // Attribute and property for the

source/code/projects/AList/AList/Program.cs

@@ -122,7 +122,16 @@ static void Main(string[] args)
     {
       Console.WriteLine(ex.Message);
     }
+    try
+    {
+      myList1.Clear();
+    }
+    catch (Exception ex)
+    {
+      Console.WriteLine(ex.Message);
+    }
 
+    /* Testing copying into an array.*/
     int[] array = new int[myList1.Count + 1];
     try
     {

source/code/projects/Tree/Tree/BTree.cs

@@ -137,4 +137,77 @@ private bool Find(Node nodeP, T dataP)
 
   public abstract void Insert(T dataP);
   public abstract bool Delete(T dataP);
+
+  /* Traversal methods. */
+  // Inorder traversal
+  // "Left, root, right"
+  public string TrasverseI()
+  {
+    string returned = "";
+    if (root != null)
+    {
+      returned += TraverseI(root);
+    }
+    return returned;
+  }
+
+  private string TraverseI(Node nodeP)
+  {
+    string returned = "";
+    if (nodeP != null)
+    {
+      returned += TraverseI(nodeP.left);
+      returned += nodeP.Data + " ";
+      returned += TraverseI(nodeP.right);
+    }
+    return returned;
+  }
+
+  // Preorder traversal
+  // "Root, left, right"
+  public string TrasversePr()
+  {
+    string returned = "";
+    if (root != null)
+    {
+      returned += TraversePr(root);
+    }
+    return returned;
+  }
+
+  private string TraversePr(Node nodeP)
+  {
+    string returned = "";
+    if (nodeP != null)
+    {
+      returned += nodeP.Data + " ";
+      returned += TraversePr(nodeP.left);
+      returned += TraversePr(nodeP.right);
+    }
+    return returned;
+  }
+
+  // Postorder traversal
+  // "Left, right, root"
+  public string TrasversePo()
+  {
+    string returned = "";
+    if (root != null)
+    {
+      returned += TraversePo(root);
+    }
+    return returned;
+  }
+
+  private string TraversePo(Node nodeP)
+  {
+    string returned = "";
+    if (nodeP != null)
+    {
+      returned += TraversePo(nodeP.left);
+      returned += TraversePo(nodeP.right);
+      returned += nodeP.Data + " ";
+    }
+    return returned;
+  }
 }

source/code/projects/Tree/Tree/Program.cs

@@ -18,6 +18,13 @@ static void Main()
     btree.Insert(15);
 
     Console.WriteLine(btree);
+    Console.WriteLine("Inorder traversal:");
+    Console.WriteLine(btree.TrasverseI());
+    Console.WriteLine("Preorder traversal:");
+    Console.WriteLine(btree.TrasversePr());
+    Console.WriteLine("Postorder traversal:");
+    Console.WriteLine(btree.TrasversePo());
+
     Console.WriteLine("Smallest value: " + btree.FindMin());
 
     btree.Delete(btree.FindMin());
@@ -41,5 +48,23 @@ static void Main()
     {
       Console.WriteLine(i + " occurs: " + btree.Find(i));
     }
+
+    /*
+     * Second example, we begin by clearing the tree.
+     * The purpose of this example is to illustrate that
+     * the order in which values are inserted matter.
+     */
+    btree.Clear();
+    btree.Insert(10);
+    btree.Insert(6);
+    btree.Insert(12);
+    btree.Insert(15);
+    Console.WriteLine(btree);
+    btree.Clear();
+    btree.Insert(6);
+    btree.Insert(12);
+    btree.Insert(15);
+    btree.Insert(10);
+    Console.WriteLine(btree);
   }
 }