#!/usr/bin/env python3

import fractions
import functools
import itertools


def gcd_of_permutations(n):
    ds = (int(d) for d in str(n))
    xs = (9 * abs(a - b) for a, b in itertools.combinations(ds, 2))
    return functools.reduce(fractions.gcd, xs, n)


def main():
    print(gcd_of_permutations(int(input())))


if __name__ == '__main__':
    main()