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>
a = raw_input().rstrip()
b= raw_input()
l = [ 0 for _ in range(10)]
for x in b:
    if x in "7532":
        l[int(x)] += 1
    elif x == "4":
        l[3] += 1
        l[2] += 2
    elif x == "6":
        l[5] += 1
        l[3] += 1
    elif x == "8":
        l[7] += 1
        l[2] += 3
    elif x=="9":
        l[3] += 2
        l[7] += 1
        l[2] += 1
    else:
        pass
acc = []
for x in range(9, 0, -1):
    for y in range(l[x]):
        acc.append(str(x))
print("".join(acc))
