leetcode 117. Populating Next Right Pointers in Each Node II

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    7After calling your function, the tree should look like:         1 -> NULL       /  \      2 -> 3 -> NULL     / \    \    4-> 5 -> 7 -> NULLSubscribe to see which companies asked this question.

如果按照上一题的解法，那就需要去寻找next的位置
这里需要注意的是先做右子树，再做左子树
比较清晰易懂的解法

public class Solution {    public void connect(TreeLinkNode root) {        if(root==null) return;        TreeLinkNode right =null ;        if(root.left!=null&&root.right!=null){            root.left.next = root.right;            root.right.next = getNext(root.next);        }else{            if(root.left!=null) right = root.left;            if(root.right!=null) right = root.right;            if(right!=null) right.next = getNext(root.next);        }        // connect(root.next);        connect(root.right);        connect(root.left);    }    TreeLinkNode getNext(TreeLinkNode p){        if(p==null) return null;        if(p.left!=null){            return p.left;        }else if(p.right!=null){            return p.right;        }else{            return getNext(p.next);        }    }}