#include<stdio.h>
char s[200005];
long long int dp[200005];
int main()
{
	long long int n;
	scanf("%lld", &n);
	if (n % 10 > 0)
	{
		printf("0\n");
		return 0;
	}
	long long int i, k;
	scanf("%s", s);
	const long long int p = 998244353;
	for (i = 1; i <= n; i++)
		dp[i] = 0;
	dp[0] = 1;
	for (i = 0; i < n; i += 10)
	{
		if (dp[i] == 0)
			continue;
		for (k = 1; i + 10 * k <= n; k++)
			if (s[i + 2 * k] == 'o' && s[i + 5 * k] == 'o' && s[i + 10 * k] == 'o')
				dp[i + 10 * k] = (dp[i + 10 * k] + dp[i]) % p;
	}
	printf("%lld\n", dp[n]);
	return 0;
}