# 117 Populating Next Right Pointers in Each Node II

### Problem

Follow up for problem "Populating Next Right Pointers in Each Node".

What if the given tree could be any binary tree? Would your previous solution still work?

Note:

You may only use constant extra space. For example, Given the following binary tree,

``````         1
/  \
2    3
/ \    \
4   5    7
``````

After calling your function, the tree should look like:

``````         1 -> NULL
/  \
2 -> 3 -> NULL
/ \    \
4-> 5 -> 7 -> NULL
``````

### Solutions

``````/**
* Definition for binary tree with next pointer.
*     int val;
*     TreeLinkNode(int x) { val = x; }
* }
*/
public class Solution {
if (root == null) {
return;
}
while (node != null) {
if (node.left != null) {
next = node.left;
break;
}
else if (node.right != null) {
next = node.right;
break;
}
else {
node = node.next;
}
}
if (root.left != null) {
if (root.right != null) {
root.left.next = root.right;
}
else {
root.left.next = next;
}
}
if (root.right != null) {
root.right.next = next;
}

connect(root.right);
connect(root.left);
}
}
``````
``````/**
* Definition for binary tree with next pointer.
*     int val;
*     TreeLinkNode(int x) { val = x; }
* }
*/
public class Solution {
while (root != null) {
if (root.left != null) {
node.next = root.left;
node = node.next;
}
if (root.right != null) {
node.next = root.right;
node = node.next;
}
root = root.next;
if (root == null) {