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()
numbers = {}
for i in range(10):
    numbers[str(i)] = 0
for d in a:
    if d == '0': continue
    if d == '1': continue
    numbers[d] += 1

for n in numbers:
    if n == '9':
        numbers['7'] += numbers[n]
        numbers['3'] += numbers[n]*2
        numbers['2'] += numbers[n]
        numbers[n] = 0
    if n == '8':
        numbers['7'] += numbers[n]
        numbers['2'] += numbers[n]*3
        numbers[n] = 0
    if n == '6':
        numbers['5'] += numbers[n]
        numbers['3'] += numbers[n]
        numbers[n] = 0
    if n == '4':
        numbers['3'] += numbers[n]
        numbers['2'] += numbers[n]*2
        numbers[n] = 0

ans = ''
for n in sorted(numbers, reverse=True):
    ans += n*numbers[n]

print ans