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 = list(raw_input())
a = [int(x) for x in a]

b = []
for x in a:
    if x == 0 or x == 1:
        continue
    else:
        b.append(x)

numof = [0] * 10

for x in b:
    if x == 2:
        numof[2] += 1
    elif x == 3:
        numof[3] += 1
    elif x == 4:
        numof[3] += 1
        numof[2] += 2
    elif x == 5:
        numof[5] += 1
    elif x == 6:
        numof[5] += 1
        numof[3] += 1
    elif x == 7:
        numof[7] += 1
    elif x == 8:
        numof[7] += 1
        numof[2] += 3
    elif x == 9:
        numof[7] += 1
        numof[2] += 1
        numof[3] += 2

ans = []
for i in range(10):
    if numof[i] != 0:
        for j in range(numof[i]):
            ans.append(i)

ans = sorted(ans)
ans = reversed(ans)

ans = [str(x) for x in ans]
print "".join(ans)



























