Level-Order-Traversal

Author: git-aditya-pratap-singh

Diff for: Tree/Level-Order-Traversal.py

@@ -0,0 +1,66 @@
+class Node:
+    def __init__(self, data):
+        self.left = None
+        self.data = data                  # self.data = None because create an object at a time None arguments passed in constructor
+        self.right = None
+
+    def createTree(self, val):
+        if self.data is None:
+            self.data = val
+            return
+
+        elif self.data == val:
+            return
+
+        elif self.data > val:
+            if self.left:
+                self.left.createTree(val)         # the address of self.left transfer to self !
+            else:
+                self.left = Node(val)
+
+        elif self.data < val:
+            if self.right:
+                self.right.createTree(val)           # the address of self.right transfer to self !
+            else:
+                self.right = Node(val)
+
+    # Level-Order-Traversal (In use BFS(Breadth First Search))
+    def levelOrder(self):
+        self.level = 1             # declare a level of tree
+        Queue = []                 # here, it is Queue
+        Queue.append(self)         # Queue is stored first root node address at 0 index
+        Queue.append(None)         # Queue is stored is None at 1 index ---> [self,None]
+
+        while Queue != []:         # here, it is check your queue is empty or not
+            key = Queue.pop(0)      # here, it's remove element at index 0 and to store a key variable
+            if key is not None:       # here, it's key is not None because key is stored a root address
+                print(f"Level - {self.level} => {key.data}")
+
+                if key.left is not None:
+                    Queue.append(key.left)
+                if key.right is not None:
+                    Queue.append(key.right)
+
+            else:
+                print()    # here, it's used to newline
+                self.level += 1
+                if Queue == []:   # here, it's Queue is none as --- []
+                    break
+                else:
+                    Queue.append(None)      # here, it's Queue is stored is None ---> [None]
+
+
+if __name__ == "__main__":
+    Queue = []
+    root = Node(None)
+    while True:
+        num = int(input("\n Enter the node into Tree : "))
+        if num < 0:
+            break
+        else:
+            root.createTree(num)
+    root.levelOrder()
+
+''' Here, it is Called Breadth First Search (BFS) Algorithms in used Tree '''
+
+# ---------------- Written By : - Aditya Pratap Singh ------------------