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>
def readlist(f): return map(f, raw_input().split())
def readint(): return int(raw_input())
def printlist(l): print ' '.join(map(str, l))

def fact(d):
  if d < 2: return 1
  return d * fact(d-1)
fact = [fact(i) for i in range(0, 10)]

n = readint()
l = map(int, raw_input())
F = 1
for d in l:
  F *= fact[d]

res = [0]*10
for p in (7, 5, 3, 2):
  while F % fact[p] == 0:
    res[p] += 1
    F /= fact[p]
s = ''
for i in range(9, 1, -1):
  s += str(i)*res[i]
print s
