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>
import sys
lines = sys.stdin.readlines()
N = int(lines[0].strip())
num = lines[1].strip()
factor = {2:{2:1}, 3: {3:1}, 4:{2:2}, 5:{5:1}, 6:{2:1, 3:1}, 7:{7:1}, 8:{2:3}, 9:{3:2}}

factorial = [{}, {}]

tmp = {}
for i in range(2, 10):
    for k in factor[i].keys():
        if k not in tmp: tmp[k] = 0
        tmp[k] += factor[i][k]
    factorial.append(tmp.copy())
target = {}
for l in num:
    for k in factorial[int(l)].keys():
        if k not in target: target[k] = 0
        target[k] += factorial[int(l)][k]
res = ""
if 7 in target:
    val = target[7]
    res += "7" * val
    for k in factorial[7].keys():
        target[k] -= factorial[7][k] * val

if 5 in target and target[5] > 0:
    val = target[5]
    res += "5" * val
    for k in factorial[5].keys():
        target[k] -= factorial[5][k] * val

if 3 in target and target[3] > 0:
    val = target[3]
    res += "3" * val
    for k in factorial[3].keys():
        target[k] -= factorial[3][k] * val
if 2 in target: res += "2" * target[2] 
print(res)