#!/usr/bin/python
def segment_sieve(a, b):
    sqb = int(b ** .5)
    is_prime_small = [0, 0] + [1] * (sqb - 1)
    is_prime = [a!=1] + [1] * (b - a - 1)
    i = 2
    while i * i < b:
        if is_prime_small[i]:
            j = 2 * i
            while j * j < b:
                is_prime_small[j] = 0
                j += i
            for j in xrange(max(2, (a+i-1)/i) * i, b, i):
                is_prime[j - a] = 0
        i += 1
    return [i+a for i, p in enumerate(is_prime) if p]

digit_sum = lambda x: 9 if x%9==0 and x!=0 else x%9

from collections import namedtuple
Range = namedtuple('Range', 'left, right')

k = int(raw_input())
n = int(raw_input())
primes = segment_sieve(k, n+1)
hashes = map(digit_sum, primes)
left, right, hashes_size = 0, 0, len(hashes)
checked = [0] * 10
res = None
hamark = 0
while left < hashes_size:
    while right < hashes_size:
        x = hashes[right]
        if checked[x]:
            break
        right += 1
        checked[x] = 1
    dif = right - left
    if dif >= hamark:
        hamark = dif
        res = Range(left, right)
    x = hashes[left]
    checked[x] = 0
    left += 1
print primes[res.left]