题解 | #二叉树的下一个结点#

/*function TreeLinkNode(x){
    this.val = x;
    this.left = null;
    this.right = null;
    this.next = null;
}*/
var res = [];
function midOrder(root){
    if(root == null){
        return null;
    }
    if(root.left != null){
        midOrder(root.left);
    }
    res.push(root);
    if(root.right != null){
        midOrder(root.right);
    }
}
function GetNext(pNode)
{
    // write code here
    //先记录要寻找的节点
    let node = pNode;
    //找到树的根节点
    while(pNode.next != null){
        pNode = pNode.next;
    }
    let lastRes = null;
    midOrder(pNode);
    //循环遍历数组找 要寻找的节点
    for(let i = 0;i < res.length-1;i++){
        if(res[i].val == node.val){
            lastRes = res[i+1];
            break;
        }
    }
    //处理边界情况节点
    if( res[res.length-1].val == node.val && node.next == null){
        lastRes = null; 
    }
    return lastRes;
}
module.exports = {
    GetNext : GetNext
};