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())
s = raw_input()

a = [0 for i in range(10)]
for c in s:
    x = int(c)
    if (x == 4):
        a[2] += 2
        a[3] += 1
    elif (x == 8):
        a[7] += 1
        a[2] += 3
    elif (x == 9):
        a[7] += 1
        a[3] += 2
        a[2] += 1
    elif (x == 6):
        a[5] += 1
        a[3] += 1
    elif (x > 1):
        a[x] += 1

ans = ""
for i in range(9, -1, -1):
    ans += str(i) * a[i]

print ans