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()

mapping = {
    "0" : [],
    "1" : [],
    "2" : ["2"],
    "3" : ["3"],
    "4" : ["2", "2", "3"],
    "5" : ["5"],
    "6" : ["3", "5"],
    "7" : ["7"],
    "8" : ["2", "2", "2", "7"],
    "9" : ["2", "3", "3", "7"],
}

nums = {
    "0" : 0,
    "1" : 0,
    "2" : 0,
    "3" : 0,
    "4" : 0,
    "5" : 0,
    "6" : 0,
    "7" : 0,
    "8" : 0,
    "9" : 0,
}

for digit in a:
    for entry in mapping[digit]:
        nums[entry] += 1

ans = ""
for num in ["0","1","2","3","4","5","6","7","8","9"][::-1]:
    while nums[num] > 0:
        ans += num
        nums[num] -= 1
print ans
