BinaryTree Inorder Traversal Added by dev-jr

Author: rahuldev8

Programs/BinaryTreeInorder.java

@@ -0,0 +1,122 @@
+//Contributed by Dev jr - https://github.com/Dev-jr-8 
+
+class Solution {
+ // Function to return a list containing the inorder traversal of the tree.
+ ArrayList<Integer> inOrder(Node root) {
+ 
+ //New ArrayList to return 
+ ArrayList<Integer> li = new ArrayList<Integer>();
+ 
+ travel(root, li);
+ 
+ return li;
+ }
+ 
+ public static void travel(Node root, ArrayList<Integer> ans)
+ {
+ if(root==null) return;
+ 
+ //if there is node on left, go there
+ if(root.left!=null)travel(root.left,ans);
+ //add the element to list
+ ans.add(root.data);
+ //if there is node on right, go there
+ if(root.right!=null)travel(root.right,ans);
+ }
+ }
+ //Time Complexity : o(n)
+ //Space Complexity : o(n)
+
+ //Driver Code to test the Above Class
+ import java.util.LinkedList;
+import java.util.Queue;
+import java.io.*;
+import java.util.*;
+
+class Node {
+ int data;
+ Node left;
+ Node right;
+ Node(int data) {
+ this.data = data;
+ left = null;
+ right = null;
+ }
+}
+
+class GfG {
+
+ static Node buildTree(String str) {
+
+ if (str.length() == 0 || str.charAt(0) == 'N') {
+ return null;
+ }
+
+ String ip[] = str.split(" ");
+ // Create the root of the tree
+ Node root = new Node(Integer.parseInt(ip[0]));
+ // Push the root to the queue
+
+ Queue<Node> queue = new LinkedList<>();
+
+ queue.add(root);
+ // Starting from the second element
+
+ int i = 1;
+ while (queue.size() > 0 && i < ip.length) {
+
+ // Get and remove the front of the queue
+ Node currNode = queue.peek();
+ queue.remove();
+
+ // Get the current node's value from the string
+ String currVal = ip[i];
+
+ // If the left child is not null
+ if (!currVal.equals("N")) {
+
+ // Create the left child for the current node
+ currNode.left = new Node(Integer.parseInt(currVal));
+ // Push it to the queue
+ queue.add(currNode.left);
+ }
+
+ // For the right child
+ i++;
+ if (i >= ip.length) break;
+
+ currVal = ip[i];
+
+ // If the right child is not null
+ if (!currVal.equals("N")) {
+
+ // Create the right child for the current node
+ currNode.right = new Node(Integer.parseInt(currVal));
+
+ // Push it to the queue
+ queue.add(currNode.right);
+ }
+ i++;
+ }
+
+ return root;
+ }
+
+ public static void main(String[] args) throws IOException {
+ BufferedReader br =
+ new BufferedReader(new InputStreamReader(System.in));
+
+ int t = Integer.parseInt(br.readLine());
+
+ while (t > 0) {
+ String s = br.readLine();
+ Node root = buildTree(s);
+ Solution g = new Solution();
+ ArrayList<Integer> res = g.inOrder(root);
+ for (int i = 0; i < res.size(); i++)
+ System.out.print(res.get(i) + " ");
+ System.out.print("\n");
+ t--;
+ }
+ }
+}