题解 | #从上往下打印二叉树#

/* function TreeNode(x) {
    this.val = x;
    this.left = null;
    this.right = null;
} */
function PrintFromTopToBottom(root)
{
    // write code here
    let queue = [];
    let res = [];
    if(root == null)
        return [];
    queue.push(root);
    
    while(queue.length != 0){
        // let temp = queue[0];
        
        let temp = queue.shift();
        res.push(temp.val);
        if(temp.left){
            queue.push(temp.left)
        }
        if(temp.right){
            queue.push(temp.right)
        }
    }
    return res
}
module.exports = {
    PrintFromTopToBottom : PrintFromTopToBottom
};