using System;
using System.IO;
using System.Linq;
using System.Text;
using System.Collections.Generic;
using System.Diagnostics;
using System.Numerics;
using Enu = System.Linq.Enumerable;
using System.Text.RegularExpressions;

class Program
{
    public void Solve()
    {
        int H = Reader.Int(), W = Reader.Int();
        var grid = Reader.StringArray(H);
        var uf = new UnionFind(H * W);
        Func<int, int, bool> IsInside = (r, c) => r >= 0 && r < H && c >= 0 && c < W;
        var rectDic = new Dictionary<int, Rect>();

        for (int r = 0; r < H; r++)
            for (int c = 0; c < W; c++)
                if (grid[r][c] == 'x')
                    for (int dr = -1; dr <= 1; dr++)
                        for (int dc = -1; dc <= 1; dc++)
                        {
                            if (dr == 0 && dc == 0) continue;
                            int nr = r + dr, nc = c + dc;
                            if (IsInside(nr, nc) && grid[nr][nc] == 'x') uf.Unite(r * W + c, nr * W + nc);
                        }
        for (int r = 0; r < H; r++)
            for (int c = 0; c < W; c++)
                if (grid[r][c] == 'x')
                {
                    int id = uf.Root(r * W + c);
                    if (!rectDic.ContainsKey(id)) rectDic[id] = new Rect(id);
                    rectDic[id].UpdateY(r);
                    rectDic[id].UpdateX(c);
                }
        var rects = rectDic.Values.ToArray();
        int[] numElements = rectDic.Keys.Select(id => uf.NumElements(id)).ToArray();
        int N = rects.Length;
        int[] parent = Enu.Repeat(-1, N).ToArray();
        var bucket = new Dictionary<int, List<int>>();
        const int Big = 10000, Div = 100;
        Func<int, int, int> BucketId = (x, y) => x / Div * Big + y / Div;

        for (int i = 0; i < N; i++)
        {
            int id = BucketId(rects[i].X1, rects[i].Y1);
            if (!bucket.ContainsKey(id)) bucket[id] = new List<int>();
            bucket[id].Add(i);
        }
        for (int a = 0; a < N; a++)
        {
            int x = rects[a].X1 / Div;
            int y = rects[a].Y1 / Div;
            for (; x <= rects[a].X2 / Div + 1; x++)
                for (; y <= rects[a].Y2 / Div + 1; y++)
                {
                    int id = x * Big + y;
                    if (!bucket.ContainsKey(id)) continue;
                    foreach (int b in bucket[id])
                        if (rects[b].IsInside(rects[a]))
                        {
                            if (parent[b] == -1 || rects[a].IsInside(rects[parent[b]]))
                                parent[b] = a;
                        }
                }
        }
        var G = Enu.Range(0, N).Select(i => new List<int>()).ToArray();
        for (int i = 0; i < N; i++)
            if (parent[i] != -1)
                G[parent[i]].Add(i);
        memo = new int?[N, 2];
        int ans = 0;
        for (int i = 0; i < N; i++)
            if (parent[i] == -1)
                ans += Rec(i, 1, numElements, G);

        Console.WriteLine(ans);
    }


    int?[,] memo;
    private int Rec(int i, int canUse, int[] numElements, List<int>[] G)
    {
        if (memo[i, canUse].HasValue) return memo[i, canUse].Value;
        int res = 0;

        foreach (int child in G[i])
            res += Rec(child, 1, numElements, G);
        if (canUse == 1)
        {
            int other = numElements[i];
            foreach (int child in G[i])
                other += Rec(child, 0, numElements, G);
            res = Math.Max(res, other);
        }

        memo[i, canUse] = res;
        return res;
    }

    class Rect
    {
        public int Id;
        public int X1 = int.MaxValue, X2 = int.MinValue;
        public int Y1 = int.MaxValue, Y2 = int.MinValue;

        public Rect(int id) { Id = id; }

        public void UpdateX(int x)
        {
            X1 = Math.Min(X1, x);
            X2 = Math.Max(X2, x);
        }
        public void UpdateY(int y)
        {
            Y1 = Math.Min(Y1, y);
            Y2 = Math.Max(Y2, y);
        }
        public bool IsInside(Rect b)
        {
            return X1 > b.X1 && X2 < b.X2 && Y1 > b.Y1 && Y2 < b.Y2;
        }
    }


    class UnionFind
    {
        private int[] parent;
        private int[] rank;
        private int[] numElements;

        public UnionFind(int N)
        {
            parent = new int[N];
            rank = new int[N];
            numElements = new int[N];
            for (int i = 0; i < N; i++)
            {
                parent[i] = i;
                numElements[i] = 1;
            }
        }
        public int Root(int x)
        {
            if (parent[x] == x) return x;
            return parent[x] = Root(parent[x]);
        }
        public bool Same(int x, int y)
        {
            return Root(x) == Root(y);
        }
        public int NumElements(int x)
        {
            return numElements[Root(x)];
        }
        public bool Unite(int x, int y)
        {
            x = Root(x); y = Root(y);
            if (x == y) return false;
            if (rank[x] > rank[y]) { var t = x; x = y; y = t; }
            if (rank[x] == rank[y]) rank[y]++;
            parent[x] = y;
            numElements[y] += numElements[x];
            return true;
        }
        public int[][] Components()
        {
            var dic = new Dictionary<int, List<int>>();
            for (int i = 0; i < parent.Length; i++)
            {
                int root = Root(i);
                if (!dic.ContainsKey(root)) dic[root] = new List<int>();
                dic[root].Add(i);
            }
            return dic.Values.Select(c => c.ToArray()).ToArray();
        }
    }
}


class Entry { static void Main() { new Program().Solve(); } }
class Reader
{
    private static TextReader reader = Console.In;
    private static readonly char[] separator = { ' ' };
    private static readonly StringSplitOptions op = StringSplitOptions.RemoveEmptyEntries;
    private static string[] A = new string[0];
    private static int i;
    private static void Init() { A = new string[0]; }
    public static void Set(TextReader r) { reader = r; Init(); }
    public static void Set(string file) { reader = new StreamReader(file); Init(); }
    public static bool HasNext() { return CheckNext(); }
    public static string String() { return Next(); }
    public static int Int() { return int.Parse(Next()); }
    public static long Long() { return long.Parse(Next()); }
    public static double Double() { return double.Parse(Next()); }
    public static int[] IntLine() { return Array.ConvertAll(Split(Line()), int.Parse); }
    public static int[] IntArray(int N) { return Enu.Range(0, N).Select(i => Int()).ToArray(); }
    public static int[][] IntTable(int H) { return Enu.Range(0, H).Select(i => IntLine()).ToArray(); }
    public static string[] StringArray(int N) { return Enu.Range(0, N).Select(i => Next()).ToArray(); }
    public static string Line() { return reader.ReadLine().Trim(); }
    private static string[] Split(string s) { return s.Split(separator, op); }
    private static string Next() { CheckNext(); return A[i++]; }
    private static bool CheckNext()
    {
        if (i < A.Length) return true;
        string line = reader.ReadLine();
        if (line == null) return false;
        if (line == "") return CheckNext();
        A = Split(line);
        i = 0;
        return true;
    }
}