BinTree

utils/memory_array.py

@@ -1,7 +1,7 @@
 from utils.literal import Literal
 from utils.memory_cell import MemoryCell
 from utils.memory_manager import MemoryManager
-from pathlib import Path
+from utils.project_dir import get_path
 from random import randint
 
 class MemoryArray:
@@ -88,9 +88,7 @@ class MemoryArray:
     @staticmethod
     def create_array_from_file(filename, limit=None):
         """Erzeugt ein Speicherarray aus einer Datei."""
-        this_dir = Path(__file__).resolve().parent
-        project_dir = this_dir.parent
-        filename = project_dir / filename
+        filename = get_path(filename)
         with open(filename) as f:
             lines = f.readlines()
         if limit is not None:
@@ -122,3 +120,7 @@ if __name__ == "__main__":
         s += cell
     print(s)
     print(f"Anzahl der Additionen: {MemoryManager.count_adds()}")
+
+    a = MemoryArray.create_array_from_file("data/seq0.txt")
+    print(a)
+

utils/project_dir.py

@@ -0,0 +1,13 @@
+from pathlib import Path
+
+def get_path(filename) -> Path:
+    this_dir = Path(__file__).resolve().parent
+    project_dir = this_dir.parent
+    return project_dir / filename
+
+if __name__ == "__main__":
+    filename = get_path("data/seq0.txt")
+    print(filename)
+    print(filename.resolve())
+    print(filename.is_file())
+    print(filename.exists())

vorlesung/05_binaere_baeume/bin_tree.py

@@ -0,0 +1,202 @@
+from bin_tree_node import BinaryTreeNode
+from utils.project_dir import get_path
+from datetime import datetime
+
+
+class BinaryTree:
+
+    def __init__(self):
+        self.root = None
+        self.size = 0
+
+    def new_node(self, value):
+        return BinaryTreeNode(value)
+
+    def insert(self, value):
+        self.size += 1
+        if self.root is None:
+            self.root = self.new_node(value)
+            return self.root, None
+        else:
+            current = self.root
+            while True:
+                if value < current.value:
+                    if current.left:
+                        current = current.left
+                    else:
+                        current.left = self.new_node(value)
+                        return current.left, current
+                elif value >= current.value:
+                    if current.right:
+                        current = current.right
+                    else:
+                        current.right = self.new_node(value)
+                        return current.right, current
+                else:
+                    return None, None
+
+    def search(self, value):
+        current = self.root
+        while current:
+            if value < current.value:
+                current = current.left
+            elif value > current.value:
+                current = current.right
+            else:
+                return current
+        return None
+
+    def delete(self, value):
+        # Der Wert wird im Baum gesucht und der erste Treffer gelöscht
+        # Rückgabe falls der Wert gefunden wird:
+        # der Knoten, der den zu löschenden Knoten ersetzt und der Elternknoten des gelöschten Knotens
+        parent = None
+        current = self.root
+        while current:
+            if value < current.value:
+                parent = current
+                current = current.left
+            elif value > current.value:
+                parent = current
+                current = current.right
+            else:
+                # Knoten gefunden
+                break
+        else:
+            # Wert nicht gefunden
+            return
+        return self.delete_node(current, parent)
+
+    def delete_node(self, current, parent):
+        # Der übergebene Knoten wird
+        # Rückgabe ist ein Tupel:
+        # der Knoten, der den zu löschenden Knoten ersetzt und der Elternknoten des gelöschten Knotens
+        self.size -= 1
+        # Fall 3: Es gibt zwei Kinder: wir suchen den Nachfolger
+        if current.left and current.right:
+            parent = current
+            successor = current.right
+            while successor.left:
+                parent = successor
+                successor = successor.left
+            # Wert des Nachfolgers wird in den Knoten geschrieben, der gelöscht werden soll
+            current.value = successor.value
+            # Ab jetzt muss successor gelöscht werden; parent ist bereits richtig gesetzt
+            current = successor
+
+        # Ermitteln des einen Kindes (falls es eines gibt), sonst None
+        # Das eine Kind ist der Ersatz für den Knoten, der gelöscht werden soll
+        if current.left:
+            child = current.left
+        else:
+            child = current.right
+
+        # Falls es keinen Elternknoten gibt, ist der Ersatzknoten die Wurzel
+        if not parent:
+            self.root = child
+            return child, None
+        elif parent.left == current:
+            parent.left = child
+            return child, parent
+        else:
+            parent.right = child
+            return child, parent
+
+
+    def in_order_traversal(self, callback):
+
+        def in_order_traversal_recursive(callback, current):
+            if current is not None:
+                in_order_traversal_recursive(callback, current.left)
+                callback(current)
+                in_order_traversal_recursive(callback, current.right)
+
+        in_order_traversal_recursive(callback, self.root)
+
+
+    def level_order_traversal(self, callback):
+        if self.root is None:
+            return
+        queue = [(self.root, 0)]
+        while queue:
+            current, level = queue.pop(0)
+            callback(current, level)
+            if current.left is not None:
+                queue.append((current.left, level + 1))
+            if current.right is not None:
+                queue.append((current.right, level + 1))
+
+    def tree_structure_traversal(self, callback):
+
+        def tree_structure_traversal_recursive(callback, current, level):
+            nonlocal line
+            if current:
+                tree_structure_traversal_recursive(callback, current.left, level + 1)
+                callback(current, level, line)
+                line += 1
+                tree_structure_traversal_recursive(callback, current.right, level + 1)
+
+        line = 0
+        tree_structure_traversal_recursive(callback, self.root, 0)
+
+
+    def graph_traversal(self):
+
+        def define_node(node, level, line):
+            nonlocal file
+            if node is not None:
+                file.write(node.gv_rep(level, line))
+
+        def graph_traversal_recursive(current):
+            nonlocal file
+            if current is not None:
+                if current.left:
+                    file.write(f"{id(current)} -> {id(current.left)}; \n")
+                    graph_traversal_recursive(current.left)
+                if current.right:
+                    file.write(f"{id(current)} -> {id(current.right)}; \n")
+                    graph_traversal_recursive(current.right)
+
+        timestamp = datetime.now().strftime("%Y%m%d_%H:%M:%S")
+        filename = f"graph_{timestamp}.gv"
+        filename = get_path(filename)
+        with open(filename, "w") as file:
+            file.write("digraph BST {\n")
+            file.write("layout=neato;\n")
+            file.write("node [shape=circle, fontname=\"Arial\"];\n")
+            self.tree_structure_traversal(define_node)
+            graph_traversal_recursive(self.root)
+            file.write("}")
+
+
+
+
+if __name__ == "__main__":
+    tree = BinaryTree()
+    values = [5, 3, 7, 2, 4, 6, 5, 8]
+
+    for value in values:
+        tree.insert(value)
+
+    def print_node(node, indent=0, line=None):
+        print((indent * 3) * " ", node.value)
+
+
+    print("In-order traversal:")
+    tree.in_order_traversal(print_node)
+    print("\nLevel-order traversal:")
+    tree.level_order_traversal(print_node)
+    print("\nTree structure traversal:")
+    tree.tree_structure_traversal(print_node)
+    print("\nGraph traversal:")
+    tree.graph_traversal()
+
+    print("\nDeleting 5:")
+    tree.delete(5)
+
+    print("In-order traversal after deletion:")
+    tree.in_order_traversal(print_node)
+    print("\nLevel-order traversal after deletion:")
+    tree.level_order_traversal(print_node)
+    print("\nTree structure traversal after deletion:")
+    tree.tree_structure_traversal(print_node)

vorlesung/05_binaere_baeume/bin_tree_node.py

@@ -0,0 +1,24 @@
+from utils.memory_cell import MemoryCell
+
+class BinaryTreeNode(MemoryCell):
+
+    def __init__(self, value):
+        super().__init__(value)
+        self.left = None
+        self.right = None
+
+    def height(self):
+        left_height = self.left.height() if self.left else 0
+        right_height = self.right.height() if self.right else 0
+        return 1 + max(left_height, right_height)
+
+    def __repr__(self):
+        return f"TreeNode(value={self.value}, left={self.left}, right={self.right})"
+
+    def __str__(self):
+        return str(self.value)
+
+    def gv_rep(self, row, col):
+        """Returns the graphviz representation of the node."""
+        return f"{id(self)} [label=\"{self.value}\", pos=\"{col},{-row}!\"];\n"
+