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())
a = raw_input().strip()
k = [0] * 10
for c in a:
    if c >= '7':
        k[7] += 1
        if c >= '8':
            k[2] += 3
        if c >= '9':
            k[3] += 2
    elif c >= '5':
        k[5] += 1
        if c >= '6':
            k[2] += 1
            k[3] += 1
    else:
        if c >= '4':
            k[2] += 2
        if c >= '3':
            k[3] += 1
        if c >= '2':
            k[2] += 1
print '7' * k[7] + '5' * k[5] + '3' * k[3] + '2' * (k[2] - k[3])
