import { Concept } from "../../DataStructures/Concept";
import { UserNode } from "./UserNode";
export declare class UserBinaryTree {
    static root: UserNode | null;
    static compositeKey(userId: number, sessionId: number): string;
    static addNodeToTree(node: UserNode): UserNode | undefined;
    static waitForDataToLoad(): Promise<unknown>;
    static checkFlag(resolve: any): any;
    static addConceptToTree(concept: Concept, userId: number, sessionId?: number): void;
    static getNodeFromTree(userId: number, sessionId: number): Promise<UserNode | null>;
    static removeNodeFromTree(userId: number, sessionId?: number): Promise<void>;
    static countNumberOfNodes(): number;
}