#include <stdio.h>

const int Mod = 998244353;

int main()
{
	int i, N;
	char S[2000002];
	scanf("%d", &N);
	for (i = 0; i < N; i++) scanf("%s", &(S[i*16+1]));

	int cur, prev;
	long long dp[2][3] = {};
	if (S[1] == '.') {
		dp[0][0] = 1;
		if (S[2] != 'd') dp[0][1] = 1;
		if (S[2] != 'k') dp[0][2] = 1;
	} else if (S[1] == 'd') dp[0][1] = 1;
	else dp[0][2] = 1;
	for (i = 2, cur = 1, prev = 0; i <= N * 16; i++, cur ^= 1, prev ^= 1) {
		if (i % 2 == 0) {
			if (S[i] == '.') {
				dp[cur][0] = (dp[prev][0] + dp[prev][1] + dp[prev][2]) % Mod;
				if (i == N * 16 || S[i+1] != 'd') dp[cur][1] = (dp[prev][1] + dp[prev][2]) % Mod;
				else dp[cur][1] = 0;
				if (i == N * 16 || S[i+1] != 'k') dp[cur][2] = (dp[prev][1] + dp[prev][2]) % Mod;
				else dp[cur][2] = 0;
			} else if (S[i] == 'd') {
				dp[cur][0] = 0;
				dp[cur][1] = (dp[prev][1] + dp[prev][2]) % Mod;
				dp[cur][2] = 0;
			} else {
				dp[cur][0] = 0;
				dp[cur][1] = 0;
				dp[cur][2] = (dp[prev][1] + dp[prev][2]) % Mod;
			}
		} else {
			if (S[i] == '.') {
				dp[cur][0] = dp[prev][0];
				if (S[i+1] != 'd') dp[cur][1] = (dp[prev][0] + dp[prev][1] + dp[prev][2]) % Mod;
				else dp[cur][1] = 0;
				if (S[i+1] != 'k') dp[cur][2] = (dp[prev][0] + dp[prev][1] + dp[prev][2]) % Mod;
				else dp[cur][2] = 0;
			} else if (S[i] == 'd') {
				dp[cur][0] = 0;
				dp[cur][1] = (dp[prev][0] + dp[prev][1] + dp[prev][2]) % Mod;
				dp[cur][2] = 0;
			} else {
				dp[cur][0] = 0;
				dp[cur][1] = 0;
				dp[cur][2] = (dp[prev][0] + dp[prev][1] + dp[prev][2]) % Mod;
			}
		}
	}
	printf("%lld\n", (dp[prev][0] + dp[prev][1] + dp[prev][2]) % Mod);
	fflush(stdout);
	return 0;
}