#include <bits/stdc++.h> using namespace std; const long long MOD = 998244353; int main(){ int H, W; cin >> H >> W; vector<string> S(H); for (int i = 0; i < H; i++){ cin >> S[i]; } vector<vector<int>> x(H + W - 1), y(H + W - 1); for (int i = 0; i < H; i++){ for (int j = 0; j < W; j++){ if (S[i][j] == '.'){ x[i + j].push_back(i); y[i + j].push_back(j); } } } vector<vector<long long>> dp = {{0, 0}, {1, 0}}; for (int i = 1; i < H + W - 2; i++){ int cnt1 = x[i].size(), cnt2 = x[i + 1].size(); vector<vector<int>> nxt(cnt1); for (int j = 0; j < cnt1; j++){ for (int k = 0; k < cnt2; k++){ if (x[i + 1][k] >= x[i][j] && x[i + 1][k] <= x[i][j] + 1){ nxt[j].push_back(k); } } } vector<vector<long long>> dp2(cnt2, vector<long long>(cnt2, 0)); for (int j = 0; j < cnt1; j++){ for (int k = 0; k < cnt1; k++){ for (int j2 : nxt[j]){ for (int k2 : nxt[k]){ if (j2 != k2 || i == H + W - 3){ dp2[j2][k2] += dp[j][k]; dp2[j2][k2] %= MOD; } } } } } dp = dp2; } cout << dp[0][0] << endl; }