I need help with this Java question: Tree: Top View. We are govegiven a code to work with and please use Java $8$ to answer the question. Please make sure your code works and provide output if you can. Here is the question.

Given a pointer to the root of a binary tree, print the top view of the binary tree.

The tree as seen from the top the nodes, is called the top view of the tree.

For example :

$\backslash$table$[[1],[1,],[2,],[1,],[5,],[11,1],[36,6],[1,],[4,]]$

Top View : $1256$

Complete the function topView and print the resulting values on a single line separated by space.

Input Format

You are given a function,

void topView$($node $*$ root$)\{$

$\}$

Constraints

$1$ Nodes in the tree $500$

Output Format

Print the values on a single line separated by space.

Sample Input

$\backslash$table$[[1],[1,],[2,],[1,],[5,],[11,1],[36,6],[1,],[4,]]$

Sample Output

$1256$

Explanation

$\backslash$table$[[1],[1,],[2,],[1,],[5,],[11,1],[36,6],[1,],[4,]]$

From the top, only nodes $1,2,5,6$ are visible.

Here is the code we are given to work with.

import java.util.$*$;

import java.io$.*$;

class Node $\{$

Node left;

Node right;

int data;

Node$($int data$)\{$

this.data $=$ data;

left $=$ null;

right $=$ null;

$\}$

$\}$

class Solution $\{$

$/*$

class Node

int data;

Node left;

Node right;

$*/$

public static void topView$($Node root$)\{$

$\}$

public static Node insert$($Node root, int data$)\{$

if$($root $==$ null$)\{$

return new Node$($data$)$;

$\}$ else $\{$

Node cur;

if$($data root.data$)\{$

cur $=$ insert$($root$.$left, data$)$;

root.left $=$ cur;

$\}$ else $\{$

cur $=$ insert$($root$.$right, data$)$;

root.right $=$ cur;

$\}$

return root;

$\}$

$\}$

public static void main$($String$[]$ args$)\{$

Scanner scan $=$ new Scanner$($System$.$in$)$;

int t $=$ scan.nextInt$()$;

Node root $=$ null;

while$($t$-->0)\{$

int data $=$ scan.nextInt$()$;

root $=$ insert$($root$,$ data$)$;

$\}$

scan.close$()$;

topView$($root$)$;

$\}$

$\}$