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>
z = [0] * 10
x = input()
s = raw_input()
for i in s:
    if i in ['7', '5', '2']:
        z[int(i)] += 1
    else:
        x = int(i)
        if x == 9:
            z[3] += 2
            z[2] += 1
            z[7] += 1
        elif x == 8:
            z[2] += 3
            z[7] += 1
        elif x == 6:
            z[3] += 1
            z[5] += 1
        elif x == 4:
            z[2] += 2
            z[3] += 1
        elif x == 3:
            z[3] += 1

ans = []
for i, j in enumerate(z):
    while z[i] > 0:
        ans.append(i)
        z[i] -= 1

ans = sorted(ans, reverse=True)
print(''.join([str(i) for i in ans]))
