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>
from collections import Counter
n = int(input())
a = input()
t = Counter()
for i in a:
    x = int(i)
    l = []
    if x == 2:
        l = [2]
    elif x == 3:
        l = [3]
    elif x == 4:
        l = [2, 2, 3]
    elif x == 5:
        l = [5]
    elif x == 6:
        l = [5, 3]
    elif x == 7:
        l = [7]
    elif x == 8:
        l = [7, 2, 2, 2]
    elif x == 9:
        l = [3, 3, 2, 7]
    t += Counter(l)
ans = []
for i in t:
    for j in range(t[i]):
        ans.append(i)
ans.sort(reverse=True)
for i in ans:
    print(i, end="")