Drazil is playing a math game with Varda.

Let's define <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7020b94c48be2ee5b8eeca05f379c8911bb0e7c4.png" style="max-width: 100.0%;max-height: 100.0%;"/> for positive integer *x* as a product of factorials of its digits. For example, <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/6784d861d9a724d0aeddefcb00b7d0c3442ae586.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

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. <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7020b94c48be2ee5b8eeca05f379c8911bb0e7c4.png" style="max-width: 100.0%;max-height: 100.0%;"/> = <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/aa57e017a6c74d06b0a54bc47e3f6990e5af38c1.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

Help friends find such number.
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.
#include <bits/stdc++.h>
#define ll long long
#define endl "\n"
#define sz(x) x.size()
#define loop(x, i, n) for (int i = x; i < n; i++)
int dx[]{1, 0, 0, -1, 1, 1, -1, -1};
int dy[]{0, 1, -1, 0, 1, -1, 1, -1};
using namespace std;
string cur[10] = {"", "", "2", "3", "223", "5", "53", "7", "7222", "7332"};
int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);

#ifndef ONLINE_JUDGE
	freopen("in.txt", "r", stdin);

#endif // ONLINE_JUDGE

	int n;
	string s, ans;
	cin >> n >> s;
	for (int i = 0; i < n; i++)
	{
		ans += cur[s[i] - '0'];
	}
	sort(ans.rbegin(), ans.rend());
	cout << ans << endl;
}