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.util.*;


import java.io.*;


public class E1511 {
    
    static int mod = 998244353;
    static InputReader in;
    static PrintWriter out;
    static long invMod = pow(9, mod - 2, mod);
    
    static long getCount(long x) {
    	x--;
    	long cnt = 0;
    	cnt = (3 * x + 1);
    	cnt %= mod;
    	cnt *= pow(2, x, mod);
    	cnt %= mod;
    	if(x % 2 == 0) {
    		cnt -= 1;
    		cnt += mod;
    	}
    	else {
    		cnt += 1;
    	}
    	cnt %= mod;
    	cnt *= invMod;
    	cnt %= mod;
    	return cnt;
    }

    static void solve()
    {
 
        in = new InputReader(System.in);
        out = new PrintWriter(System.out); 
        
        int n = in.nextInt();
        int m = in.nextInt();
        
        char[][] ch = new char[n][];
        
        long cnt = 0;
        
        for(int i = 0; i < n; i++) {
        	ch[i] = in.readString().toCharArray();
        	for(int j = 0; j < m; j++) {
        		cnt += ch[i][j] == 'o' ? 1 : 0;
        	}
        }
        
        long ans = 0;
        for(int i = 0; i < n; i++) {
        	int c = 0;
        	for(int j = 0; j < m; j++) {
        		if(ch[i][j] == 'o') {
        			c++;
        		}
        		else {
        			if(c != 0) {
        				long curr = getCount(c) * pow(2, cnt - c, mod);
        				curr %= mod;
        				ans += curr;
        				ans %= mod;
        			}
        			c = 0;
        		}
        	}
			if(c != 0) {
				long curr = getCount(c) * pow(2, cnt - c, mod);
				curr %= mod;
				ans += curr;
				ans %= mod;
			}
        }
        
        for(int j = 0; j < m; j++) {
        	int c = 0;
        	for(int i = 0; i < n; i++) {
        		if(ch[i][j] == 'o') {
        			c++;
        		}
        		else {
        			if(c != 0) {
        				long curr = getCount(c) * pow(2, cnt - c, mod);
        				curr %= mod;
        				ans += curr;
        				ans %= mod;
        			}
        			c = 0;
        		}        		
        	}
			if(c != 0) {
				long curr = getCount(c) * pow(2, cnt - c, mod);
				curr %= mod;
				ans += curr;
				ans %= mod;
			}        	
        }
        
        out.println(ans);
        out.close();
        
    }
    
    public static void main(String[] args) {
        new Thread(null ,new Runnable(){
            public void run()
            {
                try{
                    solve();
                } catch(Exception e){
                    e.printStackTrace();
                }
            }
        },"1",1<<26).start();
    }
    
    static int[][] graph(int from[], int to[], int n)
    {
        int g[][] = new int[n][];
        int cnt[] = new int[n];
        for (int i = 0; i < from.length; i++) {
            cnt[from[i]]++;
            cnt[to[i]]++;
        }
        for (int i = 0; i < n; i++) {
            g[i] = new int[cnt[i]];
        }
        Arrays.fill(cnt, 0);
        for (int i = 0; i < from.length; i++) {
            g[from[i]][cnt[from[i]]++] = to[i];
            g[to[i]][cnt[to[i]]++] = from[i];
        }
        return g;
    }
    
    static class Pair implements Comparable<Pair>{

        int x,y,z;
        
		Pair (int x,int y,int z){
			this.x=x;
			this.y=y;
			this.z=z;
		}
	        
		public int compareTo(Pair o) {
			if (this.x == o.x)
				return Integer.compare(this.y,o.y);
			return Integer.compare(this.x,o.x);
			//return 0;
		}

        public boolean equals(Object o) {
            if (o instanceof Pair) {
                Pair p = (Pair)o;
                return p.x == x && p.y == y;
            }
            return false;
        }
        public int hashCode() {
            return new Integer(x).hashCode() * 31 + new Integer(y).hashCode();
        }
        
        @Override
        public String toString() {
        	return x + " " + y;
        }
    
    } 
    
    static String rev(String s) {
        StringBuilder sb = new StringBuilder(s);
        sb.reverse();
        return sb.toString();
    }

    static long gcd(long x, long y) {
        if (y == 0) {
            return x;
        } else {
            return gcd(y, x % y);
        }
    }

    static int gcd(int x, int y) {
        if (y == 0) {
            return x;
        } else {
            return gcd(y, x % y);
        }
    }
    
    static int abs(int a, int b) {
        return (int) Math.abs(a - b);
    }

    static long abs(long a, long b) {
        return (long) Math.abs(a - b);
    }

    static int max(int a, int b) {
        if (a > b) {
            return a;
        } else {
            return b;
        }
    }

    static int min(int a, int b) {
        if (a > b) {
            return b;
        } else {
            return a;
        }
    }

    static long max(long a, long b) {
        if (a > b) {
            return a;
        } else {
            return b;
        }
    }

    static long min(long a, long b) {
        if (a > b) {
            return b;
        } else {
            return a;
        }
    }

    static long pow(long n, long p, long m) {
        long result = 1;
        if (p == 0) {
            return 1;
        }
        while (p != 0) {
            if (p % 2 == 1) {
                result *= n;
            }
            if (result >= m) {
                result %= m;
            }
            p >>= 1;
            n *= n;
            if (n >= m) {
                n %= m;
            }
        }
        return result;
    }

    static long pow(long n, long p) {
        long result = 1;
        if (p == 0) {
            return 1;
        }
        if (p == 1) {
            return n;
        }
        while (p != 0) {
            if (p % 2 == 1) {
                result *= n;
            }
            p >>= 1;
            n *= n;
        }
        return result;
    }
   
    static void debug(Object... o) {
            System.out.println(Arrays.deepToString(o));
    }

    static class InputReader
    {

        private final InputStream stream;
        private final byte[] buf = new byte[8192];
        private int curChar, snumChars;
        private SpaceCharFilter filter;

        public InputReader(InputStream stream)
        {
                this.stream = stream;
        }

        public int snext()
        {
                if (snumChars == -1)
                        throw new InputMismatchException();
                if (curChar >= snumChars)
                {
                        curChar = 0;
                        try
                        {
                                snumChars = stream.read(buf);
                        } catch (IOException e)
                        {
                                throw new InputMismatchException();
                        }
                        if (snumChars <= 0)
                                return -1;
                }
                return buf[curChar++];
        }

        public int nextInt()
        {
                int c = snext();
                while (isSpaceChar(c))
                {
                        c = snext();
                }
                int sgn = 1;
                if (c == '-')
                {
                        sgn = -1;
                        c = snext();
                }
                int res = 0;
                do
                {
                        if (c < '0' || c > '9')
                                throw new InputMismatchException();
                        res *= 10;
                        res += c - '0';
                        c = snext();
                } while (!isSpaceChar(c));
                return res * sgn;
        }

        public long nextLong()
        {
                int c = snext();
                while (isSpaceChar(c))
                {
                        c = snext();
                }
                int sgn = 1;
                if (c == '-')
                {
                        sgn = -1;
                        c = snext();
                }
                long res = 0;
                do
                {
                        if (c < '0' || c > '9')
                                throw new InputMismatchException();
                        res *= 10;
                        res += c - '0';
                        c = snext();
                } while (!isSpaceChar(c));
                return res * sgn;
        }

        public int[] nextIntArray(int n)
        {
                int a[] = new int[n];
                for (int i = 0; i < n; i++)
                {
                        a[i] = nextInt();
                }
                return a;
        }

        public long[] nextLongArray(int n)
        {
                long a[] = new long[n];
                for (int i = 0; i < n; i++)
                {
                        a[i] = nextLong();
                }
                return a;
        }

        public String readString()
        {
                int c = snext();
                while (isSpaceChar(c))
                {
                        c = snext();
                }
                StringBuilder res = new StringBuilder();
                do
                {
                        res.appendCodePoint(c);
                        c = snext();
                } while (!isSpaceChar(c));
                return res.toString();
        }

        public String nextLine()
        {
                int c = snext();
                while (isSpaceChar(c))
                        c = snext();
                StringBuilder res = new StringBuilder();
                do
                {
                        res.appendCodePoint(c);
                        c = snext();
                } while (!isEndOfLine(c));
                return res.toString();
        }

        public boolean isSpaceChar(int c)
        {
                if (filter != null)
                        return filter.isSpaceChar(c);
                return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        private boolean isEndOfLine(int c)
        {
                return c == '\n' || c == '\r' || c == -1;
        }

        public interface SpaceCharFilter
        {
                public boolean isSpaceChar(int ch);
        }

    }
}