#include "bits/stdc++.h"
#ifdef DEBUG
#include "PrettyDebug.hpp"
#else
#define debug(...) [](auto...){}(__VA_ARGS__)
#define debuga(...) [](auto...){}(__VA_ARGS__)
#endif
#define For(i,a,b) for(int i=a;i<=b;i++)
#define Rev(i,a,b) for(int i=a;i>=b;i--)
#define Fin(file) freopen(file,"r",stdin)
#define Fout(file) freopen(file,"w",stdout)
using namespace std; typedef long long ll;
constexpr int N=3e3+5;
char mp[N][N]; int n,m,U[N][N],V[N][N],f[N][N],g[N][N]; bool S[N][N],T[N][N];
signed main(){
    atexit([](){cerr<<"Time = "<<clock()<<" ms"<<endl;});
    cin>>n>>m; For(i,1,n) cin>>(mp[i]+1);
    int tt=0; For(i,1,n) For(j,1,m) tt+=(mp[i][j]=='.');
    For(i,1,n) For(j,1,m) if(mp[i][j]=='.') {
        if(i==1&&j==1) { S[i][j]=1; continue; }
        if(S[i-1][j]) S[i][j]=1;
        if(S[i][j-1]) S[i][j]=1;
    }
    if(!S[n][m]) return cout<<1ll*tt*(tt-1)/2<<'\n',0;
    int u=n,v=m; V[n][m]=1;
    while(u!=1||v!=1){
        if(S[u-1][v]) u--; else v--;
        V[u][v]=1;
    }
    For(i,1,n) For(j,1,m) S[i][j]=0;
    For(i,1,n) For(j,1,m) if(mp[i][j]=='.') {
        if(i==1&&j==1) { S[i][j]=1; continue; }
        if(S[i][j-1]) S[i][j]=1;
        if(S[i-1][j]) S[i][j]=1;
    }
    Rev(i,n,1) Rev(j,m,1) if(mp[i][j]=='.') {
        if(i==n&&j==m) { T[i][j]=1; continue; }
        if(T[i+1][j]) T[i][j]=1;
        if(T[i][j+1]) T[i][j]=1;
    }
    u=n,v=m; U[n][m]=1;
    while(u!=1||v!=1){
        debug(u,v);
        if(S[u][v-1]) v--; else u--;
        U[u][v]=1;
    }
    ll ans=0; For(i,1,n) For(j,1,m) if(U[i][j]&&V[i][j]) tt--,ans+=tt;
    debug(ans);
    For(i,1,n) For(j,1,m) if(S[i][j]) {
        if(i==1&&j==1) continue;
        if(S[i][j-1]) f[i][j]=f[i][j-1]; else f[i][j]=f[i-1][j];
        f[i][j]+=(V[i][j]&&!U[i][j]);
    }
    Rev(i,n,1) Rev(j,m,1) if(T[i][j]) {
        if(i==n&&j==m) continue;
        if(T[i+1][j]) g[i][j]=g[i+1][j]; else g[i][j]=g[i][j+1];
        g[i][j]+=(V[i][j]&&!U[i][j]);
    }
    For(i,1,n) For(j,1,m) if(U[i][j]&&!V[i][j]){
        u=i,v=j; do u--,v++; while(u>=1&&v<=m&&(!S[u][v]||!T[u][v]));
        ll res=f[u][v]+g[u][v]-(V[u][v]&&!U[u][v]); ans+=res;
        debug(i,j,u,v,res);
    }
    cout<<ans<<'\n';
    return 0;
}

// CONTINUE, NON-STOPPING, FOR CHARLIEY
// START TYPING IF YOU DON'T KNOW WHAT TO DO
// STOP TYPING IF YOU DON'T KNOW WHAT YOU'RE DOING

// Started Coding On: February 18 Sun, 11 : 00 : 04