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>
from sys import stdin, stdout
import math

factorials = [1, 1]
for i in range(2, 10):
    factorials.append(factorials[i - 1] * i)
n = int(input())
num = stdin.readline().strip()
digits = [2, 3, 4, 5, 6, 7, 8, 9]
dp = [[-1] * 362890] * 9


def solve(idx, target, actualTarget):
    if idx >= len(digits) or target > actualTarget:
        return -100000000
    if target == actualTarget:
        dp[idx][target] = 0
        return 0
    if dp[idx][target] != -1:
        return dp[idx][target]
    dp[idx][target] = max(solve(idx + 1, target, actualTarget),
                          solve(idx, target * factorials[digits[idx]], actualTarget) + 1)
    return dp[idx][target]


ans = []


def build(idx, target, actualTarget):
    if idx >= len(digits) or target > actualTarget:
        return
    if target == actualTarget:
        return
    optimal = solve(idx, target, actualTarget)
    if target * factorials[digits[idx]] > factorials[9]:
        build(idx + 1, target, actualTarget)
    if optimal == dp[idx][target * factorials[digits[idx]]] + 1:
        ans.append(digits[idx])
        build(idx, target * factorials[digits[idx]], actualTarget)
    else:
        build(idx + 1, target, actualTarget)
    return


mapping = [[1], [1]]
for i in range(len(digits)):
    ans = []
    dp = [[-1] * 362890] * 9
    solve(0, 1, factorials[digits[i]])
    build(0, 1, factorials[digits[i]])
    mapping.append(ans)

ans = []
for i in range(len(num)):
    if int(num[i]) == 0 or int(num[i]) == 1:
        continue
    else:
        for j in range(len(mapping[int(num[i])])):
            ans.append(mapping[int(num[i])][j])

ans.sort(reverse=True)
for i in range(len(ans)):
    print(ans[i], end="")
