Maximum Binary Tree II solution and explanation

class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right

def insertIntoMaxTree(root, val):
    if not root or val > root.val:
        return TreeNode(val, left=root)
    root.right = insertIntoMaxTree(root.right, val)
    return root

struct TreeNode {
    int val;
    TreeNode *left;
    TreeNode *right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};

TreeNode* insertIntoMaxTree(TreeNode* root, int val) {
    if (!root || val > root->val)
        return new TreeNode(val, root);
    root->right = insertIntoMaxTree(root->right, val);
    return root;
}

class TreeNode {
    int val;
    TreeNode left, right;
    TreeNode(int val) { this.val = val; }
}

public TreeNode insertIntoMaxTree(TreeNode root, int val) {
    TreeNode node = new TreeNode(val);
    if (root == null || val > root.val) {
        node.left = root;
        return node;
    }
    TreeNode current = root;
    while (current.right != null && current.right.val > val) {
        current = current.right;
    }
    node.left = current.right;
    current.right = node;
    return root;
}

function TreeNode(val, left = null, right = null) {
    this.val = val;
    this.left = left;
    this.right = right;
}

function insertIntoMaxTree(root, val) {
    let node = new TreeNode(val);
    if (root === null || val > root.val) {
        node.left = root;
        return node;
    }
    let cur = root;
    while (cur.right !== null && cur.right.val > val) {
        cur = cur.right;
    }
    node.left = cur.right;
    cur.right = node;
    return root;
}

/**
 * Definition for a binary tree node.
 * class TreeNode {
 *     val: number
 *     left: TreeNode | null
 *     right: TreeNode | null
 *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
 *         this.val = (val===undefined ? 0 : val)
 *         this.left = (left===undefined ? null : left)
 *         this.right = (right===undefined ? null : right)
 *     }
 * }
 */

function insertIntoMaxTree(root: TreeNode | null, val: number): TreeNode | null {
    if (!root || root.val < val) {
        return new TreeNode(val, root);
    }
    root.right = insertIntoMaxTree(root.right, val);
    return root;
}

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     struct TreeNode *left;
 *     struct TreeNode *right;
 * };
 */

struct TreeNode* insertIntoMaxTree(struct TreeNode* root, int val) {
    if (!root || root->val < val) {
        struct TreeNode* res = (struct TreeNode*) malloc(sizeof(struct TreeNode));
        res->val = val;
        res->left = root;
        res->right = NULL;
        return res;
    }
    root->right = insertIntoMaxTree(root->right, val);
    return root;
}

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func insertIntoMaxTree(root *TreeNode, val int) *TreeNode {
	if root == nil || root.Val < val {
		return &TreeNode{val, root, nil}
	}
	root.Right = insertIntoMaxTree(root.Right, val)
	return root
}

// Definition for a binary tree node.
// #[derive(Debug, PartialEq, Eq)]
// pub struct TreeNode {
//   pub val: i32,
//   pub left: Option<Rc<RefCell<TreeNode>>>,
//   pub right: Option<Rc<RefCell<TreeNode>>>,
// }
//
// impl TreeNode {
//   #[inline]
//   pub fn new(val: i32) -> Self {
//     TreeNode {
//       val,
//       left: None,
//       right: None
//     }
//   }
// }
use std::cell::RefCell;
use std::rc::Rc;
impl Solution {
    pub fn insert_into_max_tree(
        mut root: Option<Rc<RefCell<TreeNode>>>,
        val: i32,
    ) -> Option<Rc<RefCell<TreeNode>>> {
        if root.is_none() || root.as_ref().unwrap().as_ref().borrow().val < val {
            return Some(Rc::new(RefCell::new(TreeNode {
                val,
                left: root.take(),
                right: None,
            })));
        }
        {
            let mut root = root.as_ref().unwrap().as_ref().borrow_mut();
            root.right = Self::insert_into_max_tree(root.right.take(), val);
        }
        root
    }
}

/**
 * Definition for a binary tree node.
 * class TreeNode {
 *     val: number
 *     left: TreeNode | null
 *     right: TreeNode | null
 *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
 *         this.val = (val===undefined ? 0 : val)
 *         this.left = (left===undefined ? null : left)
 *         this.right = (right===undefined ? null : right)
 *     }
 * }
 */

function insertIntoMaxTree(root: TreeNode | null, val: number): TreeNode | null {
    if (root.val < val) {
        return new TreeNode(val, root);
    }
    const node = new TreeNode(val);
    let curr = root;
    while (curr.right && curr.right.val > val) {
        curr = curr.right;
    }
    node.left = curr.right;
    curr.right = node;
    return root;
}

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func insertIntoMaxTree(root *TreeNode, val int) *TreeNode {
	if root.Val < val {
		return &TreeNode{val, root, nil}
	}
	node := &TreeNode{Val: val}
	curr := root
	for curr.Right != nil && curr.Right.Val > val {
		curr = curr.Right
	}
	node.Left = curr.Right
	curr.Right = node
	return root
}