1261-find-elements-in-a-contaminated-binary-tree

/**
 * Definition for a binary tree node.
 * function TreeNode(val, left, right) {
 *     this.val = (val===undefined ? 0 : val)
 *     this.left = (left===undefined ? null : left)
 *     this.right = (right===undefined ? null : right)
 * }
 */
/**
 * @param {TreeNode} root
 */
var FindElements = function(root) {
    this.tree = root;
};

/**
 * @param {number} target
 * @return {boolean}
 */
FindElements.prototype.find = function(target) {
    let targetPath = (target+1).toString(2).slice(1);

    let pointer = this.tree;
    for(let path of targetPath){
        if(pointer === null){return false;}

        pointer = path==="0" ? pointer.left : pointer.right;
    }
    return pointer !== null;
};

/**
 * Your FindElements object will be instantiated and called as such:
 * var obj = new FindElements(root)
 * var param_1 = obj.find(target)
 */