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

# sys.stdin = open('input.txt', 'r')
# sys.stdout = open('output.txt', 'w')

n = int(input())
dig = list(input())

exp = {0:[], 1:[], 2:[2], 3:[3], 4:[3, 2, 2], 5:[5], 6:[5, 3],
        7:[7], 8:[7, 2, 2, 2], 9:[7, 2, 3, 3]}
ans = []
for digit in dig:
    ans.extend(exp[int(digit)])

ans.sort(reverse=True)
print(*ans, sep='')

