trees organized

src/trees/binary_search_tree.py

@@ -1,73 +1,103 @@
 #!/usr/bin/python
 
-__author__ = "Mari Wahl"
-__email__ = "marina.w4hl@gmail.com"
+__author__ = "bt3"
 
 
-from binary_tree import NodeBT, BinaryTree
+class Node(object):
 
+    def __init__(self, item=None,):
 
-class NodeBST(NodeBT):
-
-    def __init__(self, item=None, level=0):
         self.item = item
-        self.level = level
         self.left = None
         self.right = None
 
+    def __repr__(self):
+        return '{}'.format(self.item)
+
+
+    def _add(self, value):
+        new_node = Node(value)
 
-    def _addNextNode(self, value, level_here=1):
-        new_node = NodeBST(value, level_here)
         if not self.item:
             self.item = new_node
+
         else:
             if value > self.item:
-                self.right = self.right and self.right._addNextNode(value, level_here+1) or new_node
+                self.right = self.right and self.right._add(value) or new_node
             elif value < self.item:
-                self.left = self.left and self.left._addNextNode(value, level_here+1) or new_node
+                self.left = self.left and self.left._add(value) or new_node
             else:
                 print("BSTs do not support repeated items.")
+
         return self # this is necessary!!!
 
 
-
-    def _searchForNode(self, value):
+    def _search(self, value):
         if self.item == value:
-            return self
+            return True # or self
+
         elif self.left and value < self.item:
-                return self.left._searchForNode(value)
+                return self.left._search(value)
+
         elif self.right and value > self.item:
-                return self.right._searchForNode(value)
+                return self.right._search(value)
+
         else:
             return False
 
 
+    def _isLeaf(self):
+        return not self.right and not self.left
 
-class BinarySearchTree(BinaryTree):
+
+    def _printPreorder(self):
+        print self.item
+
+        if self.left:
+            return self.left._printPreorder()
+
+        if self.right:
+            return self.right._printPreorder()
+
+
+
+class BST(object):
 
     def __init__(self):
         self.root = None
 
-    def addNode(self, value):
+    def add(self, value):
         if not self.root:
-            self.root = NodeBST(value)
+            self.root = Node(value)
         else:
-            self.root._addNextNode(value)
+            self.root._add(value)
 
+    def printPreorder(self):
+        if self.root:
+            self.root._printPreorder()
+
+    def search(self, value):
+        if self.root:
+            return self.root._search(value)
 
 
 
 if __name__ == '__main__':
-    bst = BinarySearchTree()
+
+    bst = BST()
     print "Adding nodes 1 to 10 in the tree..."
-    for i in range(1, 10):
-        bst.addNode(i)
-    print "Is 8 a leaf? ", bst.isLeaf(8)
-    print "Whats the level of node 8? ", bst.getNodeLevel(8)
-    print "Is node 10 a root? ", bst.isRoot(10)
-    print "Is node 1 a root? ", bst.isRoot(1)
-    print "Whats the tree height? ", bst.getHeight()
-    print "Is this tree BST? ", bst.isBST()
-    print "Is this tree balanced? ", bst.isBalanced()
+    for i in range(1, 11):
+        bst.add(i)
+
+    print
+    print "Searching for nodes 16 and 6"
+    print bst.search(16)
+    print bst.search(6)
+
+    print
+    print "Printing preorder..."
+    bst.printPreorder()
+
+