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(input())
s = input()
aa = [int(s[i]) for i in range(len(s)) if int(s[i]) > 1]
a = []

for i in range(len(aa)):
    if aa[i] == 4:
        a.append(2)
        a.append(2)
        a.append(3)
    elif aa[i] == 6:
        a.append(3)
        a.append(5)
    elif aa[i] == 8:
        a.append(7)
        a.append(2)
        a.append(2)
        a.append(2)
    elif aa[i] == 9:
        a.append(7)
        a.append(2)
        a.append(3)
        a.append(3)
        
    else:
        a.append(aa[i])

a.sort()
a.reverse()

for i in range(len(a)):
    print(a[i], end='')
