Merge pull request #53 from divyashukla18/patch-2

Sum of nodes.java

Sum of nodes.java

@@ -0,0 +1,63 @@
+public class SumOfNodes {  
+
+      //Represent the node of binary tree  
+        public static class Node{  
+        int data;  
+        Node left;  
+        Node right;  
+
+        public Node(int data){  
+            //Assign data to the new node, set left and right children to null  
+            this.data = data;  
+            this.left = null;  
+            this.right = null;  
+        }  
+      }  
+
+      //Represent the root of binary tree  
+      public Node root;  
+
+      public SumOfNodes(){  
+        root = null;  
+      }  
+
+      //calculateSum() will calculate the sum of all the nodes present in the binary tree  
+      public int calculateSum(Node temp){  
+        int sum, sumLeft, sumRight;  
+        sum = sumRight = sumLeft = 0;  
+
+        //Check whether tree is empty  
+        if(root == null) {  
+            System.out.println("Tree is empty");  
+            return 0;  
+        }  
+        else {  
+            //Calculate the sum of nodes present in left subtree  
+            if(temp.left != null)  
+                sumLeft = calculateSum(temp.left);  
+
+            //Calculate the sum of nodes present in right subtree  
+            if(temp.right != null)  
+                sumRight = calculateSum(temp.right);  
+
+            //Calculate the sum of all nodes by adding sumLeft, sumRight and root node's data  
+            sum = temp.data + sumLeft + sumRight;  
+            return sum;  
+        }  
+      }  
+
+      public static void main(String[] args) {  
+
+        SumOfNodes bt = new SumOfNodes();  
+        //Add nodes to the binary tree  
+        bt.root = new Node(5);  
+        bt.root.left = new Node(2);  
+        bt.root.right = new Node(9);  
+        bt.root.left.left = new Node(1);  
+        bt.root.right.left = new Node(8);  
+        bt.root.right.right = new Node(6);  
+
+        //Display the sum of all the nodes in the given binary tree  
+        System.out.println("Sum of all nodes of binary tree: " + bt.calculateSum(bt.root));  
+      }  
+    }