#include <iostream>
#include <vector>
#include <algorithm>
#include <climits>
#include <queue>
#include <set>
#include <map>

using namespace std;
using ll = long long;

signed main()
{
	{
		ios_base::sync_with_stdio(0);
		cin.tie(0);
		cout.tie(0);
	}

	int n = 26;
	ll ans = 1;
	int m = 0;
	int s;
	cin >> s;
	for (int i = 0; i < s; i++)
	{
		char next;
		cin >> next;
		if (next == '_')
		{
			m++;
		}
		else
		{
			n--;
		}
	}
	for (int i = 0; i < m; i++)
	{
		ans *= n;
		n--;
	}
	cout << ans << "\n";
}