#include<bits/stdc++.h>
using namespace std;
#define i64 __int128
#define db double
#define ldb long double
#define ull unsigned long long
#define ll long long
#define pb push_back
#define fi first
#define se second
#define pii pair<int,int>
#define lowbit(i) (i&-i) 
const int N = 3003;
ll n,m,use[N][N],vis[N][N],f[2][N][N],cnt,ans;
char s[N][N];
vector<pii> vec[N*2];
int main(){
    ios::sync_with_stdio(0);
    cin.tie(0),cout.tie(0);
    cin >> n >> m;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=m;j++){
            cin >> s[i][j];
            cnt += (s[i][j]=='.');
        }
    }
    queue<pii> q;
    if(s[1][1]=='.') q.push({1,1}),use[1][1] = 1;
    while(q.size()){
        int x = q.front().fi,y = q.front().se;
        vis[x][y]++,q.pop();
        if(s[x+1][y]=='.' && !use[x+1][y]) q.push({x+1,y}),use[x+1][y] = 1;
        if(s[x][y+1]=='.' && !use[x][y+1]) q.push({x,y+1}),use[x][y+1] = 1;
    }
    for(int i=1;i<=n;i++) for(int j=1;j<=m;j++) use[i][j] = 0;
    if(s[n][m]=='.') q.push({n,m}),use[n][m] = 1;
    while(q.size()){
        int x = q.front().fi,y = q.front().se;
        vis[x][y]++,q.pop();
        if(s[x-1][y]=='.' && !use[x-1][y]) q.push({x-1,y}),use[x-1][y] = 1;
        if(s[x][y-1]=='.' && !use[x][y-1]) q.push({x,y-1}),use[x][y-1] = 1;
    }
    for(int i=1;i<=n;i++){
        for(int j=1;j<=m;j++){
            if(vis[i][j]==2) vis[i][j] = 1;
            else vis[i][j] = 0;
        }
    }
    if(!vis[n][m] || !vis[1][1]){
        cout << cnt*(cnt-1)/2;
        exit(0);
    }
    for(int i=1;i<=n;i++){
        for(int j=1;j<=m;j++){
            if(vis[i][j]) vec[i+j].pb({i,j});
        }
    }
    int t = 0;
    for(int i=2;i<=n+m;i++){
        int siz = vec[i].size();
        if(siz==1) t++,ans += (cnt-t);
        f[0][vec[i][0].fi][vec[i][0].se] = f[1][vec[i].back().fi][vec[i].back().se] = 1;
    }
    for(int i=2;i<=n+m;i++){
        int siz = vec[i].size();
        if(siz<=1) continue;
        int x,y;
        x = vec[i][1].fi,y = vec[i][1].se;
        while(1){
            if(vec[x+y].size()>1) ans += f[1][x][y];
            if(x==n && y==m) break;
            if(vis[x][y+1]) y = y+1;
            else x = x+1;
        }
        x = vec[i][siz-2].fi,y = vec[i][siz-2].se;
        while(1){
            if(vec[x+y].size()>1) ans += f[0][x][y];
            if(x==n && y==m) break;
            if(vis[x+1][y]) x = x+1;
            else y = y+1;
        }
        if(siz==2) ans--;
    }
    cout << ans;
    return 0;
}