Problem: You have a large rectangular board which is divided into n × m cells (the board has n rows and m columns). Each cell is either white or black.

You paint each white cell either red or blue. Obviously, the number of different ways to paint them is 2^w, where w is the number of white cells.

After painting the white cells of the board, you want to place the maximum number of dominoes on it, according to the following rules:

  * each domino covers two adjacent cells; 
  * each cell is covered by at most one domino; 
  * if a domino is placed horizontally (it covers two adjacent cells in one of the rows), it should cover only red cells; 
  * if a domino is placed vertically (it covers two adjacent cells in one of the columns), it should cover only blue cells. 



Let the value of the board be the maximum number of dominoes you can place. Calculate the sum of values of the board over all 2^w possible ways to paint it. Since it can be huge, print it modulo 998 244 353.

Input

The first line contains two integers n and m (1 ≤ n, m ≤ 3 ⋅ 10^5; nm ≤ 3 ⋅ 10^5) — the number of rows and columns, respectively.

Then n lines follow, each line contains a string of m characters. The j-th character in the i-th string is * if the j-th cell in the i-th row is black; otherwise, that character is o.

Output

Print one integer — the sum of values of the board over all 2^w possible ways to paint it, taken modulo 998 244 353.

Examples

Input


3 4
**oo
oo*o
**oo


Output


144


Input


3 4
**oo
oo**
**oo


Output


48


Input


2 2
oo
o*


Output


4


Input


1 4
oooo


Output


9

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;
 
import java.math.*;
import java.awt.Point;
 
public class Main {
    //static final long MOD = 1000000007L;
    //static final long MOD2 = 1000000009L;
    static final long MOD = 998244353L;
    //static final long INF = 500000000000L;
    static final int INF =   1000000005;
    static final int NINF = -1000000005;
    //static final long NINF = -1000000000000000000L;
    static FastScanner sc;
    static PrintWriter pw;
    static final int[][] dirs = {{-1,0},{1,0},{0,-1},{0,1}};


    
    public static void main(String[] args) {
        sc = new FastScanner();
        pw = new PrintWriter(System.out);

        int Q = 1;
        for (int q = 0; q < Q; q++) {
            int N = sc.ni();
            int M = sc.ni();

            long[] dp = new long[300001];
            dp[2] = 1;
            dp[3] = 3;
            long s = 4;
            long e = 1;
            long o = 2;
            for (int i = 4; i <= 300000; i++) {
                if (i%2==0) {
                    e = (e+pow(2,i-2))%MOD;
                    dp[i] = (s+e)%MOD;
                } else {
                    o = (o+pow(2,i-2))%MOD;
                    dp[i] = (s+o)%MOD;
                }
                s = (s+dp[i])%MOD;
            }

            char[][] grid = new char[N][M];
            int sum = 0;
            for (int i = 0; i < N; i++) {
                grid[i] = sc.next().toCharArray();
                for (char c: grid[i]) {
                    if (c=='o') sum++;
                }
            }

            long ans = 0L;

            for (int i = 0; i < N; i++) {
                int c = 0;
                for (int j = 0; j < M; j++) {
                    if (grid[i][j]=='o')
                        c++;
                    else {
                        ans = (ans + dp[c]*pow(2,sum-c))%MOD;
                        c = 0;
                    }
                }
                ans = (ans + dp[c]*pow(2,sum-c))%MOD;
            }
            for (int j = 0; j < M; j++) {
                int c = 0;
                for (int i = 0; i < N; i++) {
                    if (grid[i][j]=='o')
                        c++;
                    else {
                        ans = (ans + dp[c]*pow(2,sum-c))%MOD;
                        c = 0;
                    }
                }
                ans = (ans + dp[c]*pow(2,sum-c))%MOD;
            }

            pw.println(ans);
        }
        pw.close();
    }

    public static long pow(long x, long y) {
        long ans = 1;
        x %= MOD;
        while (y > 0) {
          if((y&1)==1)
            ans = (ans * x) % MOD;
          y /= 2;
          x = (x * x) % MOD;
        }
        return ans;
    }


    public static void sort(int[] arr) {
        Random rgen = new Random();
        for (int i = 0; i < arr.length; i++) {
            int r = rgen.nextInt(arr.length);
            int temp = arr[i];
            arr[i] = arr[r];
            arr[r] = temp;
        }
        Arrays.sort(arr);
    }

    public static void sort(long[] arr) {
        Random rgen = new Random();
        for (int i = 0; i < arr.length; i++) {
            int r = rgen.nextInt(arr.length);
            long temp = arr[i];
            arr[i] = arr[r];
            arr[r] = temp;
        }
        Arrays.sort(arr);
    }

    //Sort an array (immune to quicksort TLE)
    public static void sort(int[][] arr) {
        Random rgen = new Random();
        for (int i = 0; i < arr.length; i++) {
            int r = rgen.nextInt(arr.length);
            int[] temp = arr[i];
            arr[i] = arr[r];
            arr[r] = temp;
        }
        Arrays.sort(arr, new Comparator<int[]>() {
            @Override
            public int compare(int[] a, int[] b) {
                return a[0]-b[0];
                //Ascending order.
            }
        });
    }
    
    public static void sort(long[][] arr) {
        Random rgen = new Random();
        for (int i = 0; i < arr.length; i++) {
            int r = rgen.nextInt(arr.length);
            long[] temp = arr[i];
            arr[i] = arr[r];
            arr[r] = temp;
        }
        Arrays.sort(arr, new Comparator<long[]>() {
            @Override
            public int compare(long[] a, long[] b) {
                if (a[0] > b[0])
                    return 1;
                else if (a[0] < b[0])
                    return -1;
                else
                    return 0;
                //Ascending order.
            }
        });
    }

    static class FastScanner {
        BufferedReader br;
        StringTokenizer st;
 
        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in), 32768);
            st = null;
        }
 
        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }
 
        int ni() {
            return Integer.parseInt(next());
        }

        int[][] graph(int N, int[][] edges) {
            int[][] graph = new int[N][];
            int[] sz = new int[N];
            for (int[] e: edges) {
                sz[e[0]] += 1;
                sz[e[1]] += 1;
            }
            for (int i = 0; i < N; i++) {
                graph[i] = new int[sz[i]];
            }
            int[] cur = new int[N];
            for (int[] e: edges) {
                graph[e[0]][cur[e[0]]] = e[1];
                graph[e[1]][cur[e[1]]] = e[0];
                cur[e[0]] += 1;
                cur[e[1]] += 1;
            }
            return graph;
        }
 
        int[] intArray(int N, int mod) {
            int[] ret = new int[N];
            for (int i = 0; i < N; i++)
                ret[i] = ni()+mod;
            return ret;
        }
 
        long nl() {
            return Long.parseLong(next());
        }
 
        long[] longArray(int N, long mod) {
            long[] ret = new long[N];
            for (int i = 0; i < N; i++)
                ret[i] = nl()+mod;
            return ret;
        }
 
        double nd() {
            return Double.parseDouble(next());
        }
 
        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
}