interface ChallengeTask {
    number: number;
    input: string;
}
interface TaskMessage {
    type: 'task';
    taskId: number;
    task: ChallengeTask;
    difficulty: number;
}
declare const encoder: TextEncoder;
declare function solve(inputBase64: string, difficulty: number): Promise<string>;
declare function base64ToBytes(b64: string): Uint8Array;
declare function countLeadingZeroBits(bytes: Uint8Array): number;