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>
fact = {i:0 for i in [2,3,5,7]}
n = int(raw_input())
a = raw_input()
for ai in a:
    ai = int(ai)
    if ai in [2,3,5,7]: fact[ai] += 1
    elif ai == 4:
        fact[2] += 2
        fact[3] += 1
    elif ai == 6:
        fact[3] += 1
        fact[5] += 1
    elif ai == 8:
        fact[2] += 3
        fact[7] += 1
    elif ai == 9:
        fact[2] += 1
        fact[3] += 2
        fact[7] += 1
ans = ""
for i in [7,5,3,2]:
    ans += str(i)*fact[i]
print ans    
