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>
qts = [0] * 10
n = int(raw_input())
digs = raw_input()
answer = 0l
            
for i in range(n):
  x = int(digs[i]) % 10
  if (x <= 1): continue
  elif (x == 2 or x == 3 or x == 5 or x== 7):
    qts[x] += 1
  elif (x == 6):
    qts[5] += 1
    qts[3] += 1
  elif (x == 4):
    qts[2] += 2
    qts[3] += 1
  elif (x == 9): 
    qts[2] += 1
    qts[7] += 1
    qts[3] += 2
  elif (x == 8):
    qts[7] += 1
    qts[2] += 3

    
for i in range(9, 1, -1):
  while (qts[i] > 0):
    answer += long(i)
    answer *= 10l
    qts[i] -= 1;
    
answer = answer // 10
print answer