export function randomNumberString(len: number): string {
    return formatNumberToString(
        randomNumber(len),
        len
    );
}

export function formatNumberToString(val: number, len: number) {
    return (Array(len).join('0') + val).slice(-len)
}

export function randomNumber(len: number) {
    let random = Math.random();
    let i = len;
    while (i > 0) {
        random *= 10;
        i -= 1;
    }
    return Math.floor(random)
}