//Contributed by Dev jr - https://github.com/Dev-jr-8
class Solution {
public static void travel(Node root, ArrayList 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);
}
// Function to return a list containing the inorder traversal of the tree.
ArrayList inOrder(Node root) {
//New ArrayList to return
ArrayList li = new ArrayList();
travel(root, li);
return li;
}
}
//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 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 res = g.inOrder(root);
for (int i = 0; i < res.size(); i++)
System.out.print(res.get(i) + " ");
System.out.print("\n");
t--;
}
}
}