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>
n = int(raw_input())
ss = raw_input()
fact = [0 for i in xrange(0,20)]
fact[0] = 1
for i in range(1, 11):
    fact[i] = fact[i - 1] * i
s = ""
ret = 1
for i in ss:
    ret *= fact[int(i)]
while ret % fact[7] == 0:
    s += '7'
    ret /= fact[7]
while ret % fact[5] == 0:
    s += '5'
    ret /= fact[5]
while ret % fact[3] == 0:
    s += '3'
    ret /= fact[3]
while ret % fact[2] == 0:
    s += '2'
    ret /= fact[2]
print(s)