层次遍历构建二叉树:

1.定义二叉树节点:

1 function TreeNode(val){2     this.val = val;3     this.left = this.right = null;4 }

2.层次遍历构建二叉树：

1 function createTree(arr){ 2     if(!arr||!arr.length)return null; 3     var root = new TreeNode(arr.shift()); 4     var list = [root]; 5     while(arr.length){ 6         var tmpList = []; 7         for(var i=0;i

 

 

3.测试

//var arr = [1,2,2,3,4,4,3];var arr = [1,2,2,null,3,null,3];var root = createTree(arr);console.log(root);