Drazil is playing a math game with Varda.

Let's define <image> for positive integer x as a product of factorials of its digits. For example, <image>.

First, they choose a decimal number a consisting of n digits that contains at least one digit larger than 1. This number may possibly start with leading zeroes. Then they should find maximum positive number x satisfying following two conditions:

1. x doesn't contain neither digit 0 nor digit 1.

2. <image> = <image>.

Help friends find such number.

Input

The first line contains an integer n (1 ≤ n ≤ 15) — the number of digits in a.

The second line contains n digits of a. There is at least one digit in a that is larger than 1. Number a may possibly contain leading zeroes.

Output

Output a maximum possible integer satisfying the conditions above. There should be no zeroes and ones in this number decimal representation.

Examples

Input

4
1234


Output

33222


Input

3
555


Output

555

Note

In the first case, <image>
import sys

input = sys.stdin.readline

n = int(input())
s = list(input())
s.sort()
s = s[1:]
cnt = {}

for i in range(len(s)):
    if s[i] not in cnt: cnt[s[i]] = 0
    if s[i] is '4':
        if '2' not in cnt: cnt['2'] = 0
        if '3' not in cnt: cnt['3'] = 0
        cnt['2'] += 2
        cnt['3'] += 1
    elif s[i] is '8':
        if '7' not in cnt: cnt['7'] = 0
        if '2' not in cnt: cnt['2'] = 0
        cnt['7'] += 1
        cnt['2'] += 3
    elif s[i] is '6':
        if '2' not in cnt: cnt['2'] = 0
        if '3' not in cnt: cnt['3'] = 0
        if '5' not in cnt: cnt['5'] = 0
        cnt['3'] += 1
        cnt['5'] += 1
    elif s[i] is '9':
        if '7' not in cnt: cnt['7'] = 0
        if '3' not in cnt: cnt['3'] = 0
        if '2' not in cnt: cnt['2'] = 0
        cnt['2'] += 1
        cnt['3'] += 2
        cnt['7'] += 1
    else:
        cnt[s[i]] += 1
ans = ''
for i in range(7, 1, -1):
    if str(i) in cnt:
        ans += str(i) * cnt[str(i)]
print(ans)
        