700. 二叉搜索树中的搜索

问题描述:

代码:

class Solution {
    public TreeNode searchBST(TreeNode root, int val) {
        TreeNode t = new TreeNode();
        Queue<TreeNode> tree = new LinkedList<>();
        tree.offer(root);
        while(!tree.isEmpty()){
            t=tree.poll();
            if(t.val==val)
                return t;
            if(t.left!=null)
                tree.offer(t.left);
            if(t.right!=null)
                tree.offer(t.right);
        }
        return null;
    }
}

思路:

层序遍历

701. 二叉搜索树中的插入操作

问题描述:

代码:

 

class Solution {
    public TreeNode insertIntoBST(TreeNode root, int val) {
        TreeNode t = new TreeNode();
        TreeNode v = new TreeNode(val);
        if(root==null)
            root=v;
        Queue<TreeNode> tree = new LinkedList<>();
        tree.offer(root);
        while(!tree.isEmpty()){
            t=tree.poll();
            if(t.val<v.val)
                {
                    if(t.right==null){
                        t.right=v;
                    }else{
                        tree.offer(t.right);
                    }
                }
            if(t.val>v.val){
                if(t.left==null){
                        t.left=v;
                    }else{
                        tree.offer(t.left);
                    }
            }
        }
        return root;
    }
}

思路:

层序遍历