More complete AVL, now with split and join

diff --git a/__main__.py b/__main__.py
index be26415a629f3011d1da7ce6cf3eb6ff508dcb81..a6a59a2c3e269ea98e6b4060afc496484d441a89 100644 (file)
--- a/__main__.py
+++ b/__main__.py
@@ -32,10 +32,15 @@ keys2 = {i: tree2.append(i) for i in range(25)}
 for i in range(1, 10, 3):
     keys2[i].remove()
 
-tree.join(tree2)
+tree.rjoin(tree2)
 
 print(tree)
 
+lhs_tree, rhs_tree = keys2[18].split_up()
+
+print(lhs_tree)
+print(rhs_tree)
+
 
 exit(0)
 

diff --git a/amazeing/utils/avl.py b/amazeing/utils/avl.py
index ce53209b15ad8e4159629b8ccd5c4d6136dc1068..26f2a1f47f0c42e73b1786f5436c4e42c06e332f 100644 (file)
--- a/amazeing/utils/avl.py
+++ b/amazeing/utils/avl.py
@@ -49,14 +49,21 @@ class Tree[T]:
         other.root = a
         self.root = b
 
-    def join(self, rhs: "Tree[T]") -> None:
+    def ljoin(self, lhs: "Tree[T]") -> None:
+        if self.height() >= lhs.height():
+            self.__ljoin(lhs)
+        else:
+            lhs.__rjoin(self)
+            self.exchange(lhs)
+
+    def rjoin(self, rhs: "Tree[T]") -> None:
         if self.height() >= rhs.height():
-            self.rjoin(rhs)
+            self.__rjoin(rhs)
         else:
-            rhs.ljoin(self)
+            rhs.__ljoin(self)
             self.exchange(rhs)
 
-    def ljoin(self, lhs: "Tree[T]") -> None:
+    def __ljoin(self, lhs: "Tree[T]") -> None:
         if self.root is None:
             self.exchange(lhs)
         if self.root is None or lhs.root is None:
@@ -72,7 +79,7 @@ class Tree[T]:
         new.update_height()
         new.parent.balance_one_propagate()
 
-    def rjoin(self, rhs: "Tree[T]") -> None:
+    def __rjoin(self, rhs: "Tree[T]") -> None:
         if self.root is None:
             self.exchange(rhs)
         if self.root is None or rhs.root is None:
@@ -81,7 +88,7 @@ class Tree[T]:
         insert = rhs.root
         rhs.root = None
         while isinstance(curr, Branch) and curr.height > insert.height + 1:
-            curr = curr.lhs
+            curr = curr.rhs
         parent = curr.parent
         new = Branch(curr.parent, curr.with_parent, insert.with_parent)
         parent.replace(curr, new)
@@ -103,6 +110,28 @@ class Node[T]:
             return self.parent
         return self.parent.root()
 
+    def split_up(self) -> tuple[Tree, Tree]:
+        """
+        makes self.parent empty
+        """
+        curr = self
+        lhs = Tree()
+        rhs = Tree()
+        while isinstance(curr.parent, Node):
+            curr_parent = curr.parent
+            extra = Tree()
+            if curr_parent.lhs is curr:
+                extra.root = curr_parent.rhs.with_parent(extra)
+                rhs.rjoin(extra)
+            elif curr_parent.rhs is curr:
+                extra.root = curr_parent.lhs.with_parent(extra)
+                lhs.ljoin(extra)
+            else:
+                raise Exception("Invalid AVL structure")
+            curr = curr_parent
+        curr.parent.root = None
+        return (lhs, rhs)
+
 
 class Branch[T](Node[T]):
     def __init__(