Adding Simple Solution for Problem 543 - Diameter BT

Author: Vanditg

Diameter_BT/SimpleSolution.py

@@ -0,0 +1,35 @@
+##==================================
+## Leetcode
+## Student: Vandit Jyotindra Gajjar
+## Year: 2020
+## Problem: 543
+## Problem Name: Diameter of Binary Tree         
+##===================================
+#
+#Given a binary tree, you need to compute the length of the diameter of the tree. 
+#The diameter of a binary tree is the length of the longest path between any two nodes in a tree. 
+#This path may or may not pass through the root.
+#
+#Example:
+#Given a binary tree
+#          1
+#         / \
+#        2   3
+#       / \     
+#      4   5    
+#Return 3, which is the length of the path [4,2,1,3] or [5,2,1,3].
+class Solution:
+    def diameterOfBinaryTree(self, root):
+        if root is None:	#Condition-check: If root is empty
+            return 0	#We return zero
+        left = self.length(root.left)	#Initialize left and count the length of left sub-tree
+        right = self.length(root.right)	#Initialize right and count the length of right sub-tree
+        leftDiameter = self.diameterOfBinaryTree(root.left)	#Initialize leftDiameter 
+        rightDiameter = self.diameterOfBinaryTree(root.right)	#Initialize rightDiameter
+        return max(left + right, max(leftDiameter, rightDiameter))	#We return max between these two parameters
+    
+    def length(self, root):	#Define length function 
+        if root is None:	#Condition-check: If root is empty
+            return 0	#We return zero
+        else:	#Condition-check: Else
+            return 1 + max(self.length(root.left), self.length(root.right))	#We return total length for the tree