Find Nearest Right Node in Binary Tree

给一个二叉树和一个node, 找到这个node在二叉树的右边的节点.

这个题要用层序扫描.

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    public TreeNode findNearestRightNode(TreeNode root, TreeNode u) {
        Queue<TreeNode> q = new LinkedList<>();
        q.add(root);
        while(!q.isEmpty()) {
            int size = q.size();
            boolean found = false;
            for(int i = 0; i < size; i++) {
                TreeNode node = q.poll();
                if(found)
                    return node;
                if(node.val == u.val)
                    found = true;
                if(node.left != null)
                    q.add(node.left);
                if(node.right != null)
                    q.add(node.right);
            }
        }
        return null;
    }
}

/**

* Definition for a binary tree node.

* public class TreeNode {

* int val;

* TreeNode left;

* TreeNode right;

* TreeNode() {}

* TreeNode(int val) { this.val = val; }

* TreeNode(int val, TreeNode left, TreeNode right) {

* this.val = val;

* this.left = left;

* this.right = right;

* }

class Solution {

public TreeNode findNearestRightNode(TreeNode root, TreeNode u) {

Queue<TreeNode> q = new LinkedList<>();

q.add(root);

while(!q.isEmpty()) {

int size = q.size();

boolean found = false;

for(int i = 0; i < size; i++) {

TreeNode node = q.poll();

if(found)

return node;

if(node.val == u.val)

found = true;

if(node.left != null)

q.add(node.left);

if(node.right != null)

q.add(node.right);

}

return null;

}

Find Nearest Right Node in Binary Tree

书脊

这青苔碧瓦堆, 俺曾睡风流觉, 将五十年兴亡看饱.

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