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>
#!/usr/bin/python3

import itertools as ittls
from collections import Counter

import re


def inputarray(func=int):
    return map(func, input().split())

# ---------------------------------------
# --------------------------------------

N = int(input())
A = input()

D = {2:0, 3:0, 5:0, 7:0}
for i in A:
    for j in range(2, int(i) + 1):
        if j in D:
            D[j] = D[j] + 1
        elif j == 4:
            D[2] = D[2] + 2
        elif j == 9:
            D[3] = D[3] + 2
        elif j == 8:
            D[2] = D[2] + 3
        else:
            D[2] = D[2] + 1
            D[3] = D[3] + 1

res = '7'*D[7]
D[5] = D[5] - D[7]
D[2] = D[2] - 4*D[7]
D[3] = D[3] - 2*D[7]

res = res + '5'*D[5]
D[3] = D[3] - D[5]
D[2] = D[2] - 3*D[5]

res = res + '3'*D[3]
D[2] = D[2] - D[3]

res = res + '2'*D[2]

print(res)
