#include<iostream>
using namespace std;
char a[101][101];
int i,j,n,m,maxim,sol[101][3],t[101][101],numarare;
int back(int k,int linie,int coloana)
{
    if(linie==n+1||coloana==m+1)
    {numarare=0;
    for(i=1;i<k;i++)
       numarare++;
       if(numarare>maxim)
        maxim=numarare;
    }
        else
    {sol[k][0]=0;
        sol[k][1]=linie;
        sol[k][2]=coloana;
        while(sol[k][0]<2)
        {
            sol[k][0]++;
            if(sol[k][0]==1&&a[linie+1][coloana]!='&'&&t[linie+1][coloana]==0)
                {t[linie+1][coloana]=1;
                back(k+1,linie+1,coloana);
                t[linie+1][coloana]=0;}

            if(sol[k][0]==2&&a[linie][coloana+1]!='&'&&t[linie][coloana+1]==0)
                {t[linie][coloana+1]=1;
                back(k+1,linie,coloana+1);
                t[linie][coloana+1]=0;}

        }
    }
}
int main()
{
    cout<<"n=";cin>>n;
    cout<<"m=";cin>>m;
    for(i=1;i<=n;i++)
        for(j=1;j<=m;j++)
        cin>>a[i][j];
    back(1,1,1);
    cout<<maxim<<endl;
}