#include <cstdio>
#include <cstring>
using namespace std;
int n,m,i,maxim,j;
int S[105][105];
char drum[105][105];
int max(int a,int b)
{
    return a>b?a:b;
}
int main()
{
    scanf("%d %d",&n,&m);
    for (i=1;i<=n;i++)
        scanf("%s",drum[i]+1);
    S[1][1]=1;
    for (i=1;i<=n;i++)
    {
        for (j=1;j<=m;j++)
        {
            if (S[i][j] || drum[i][j]=='&') continue;
            if (S[i-1][j] && drum[i-1][j]!='&') S[i][j]=S[i-1][j]+1;
            if (S[i][j-1] && drum[i][j-1]!='&') S[i][j]=max(S[i][j],S[i][j-1]+1);
            if (S[i][j]>maxim) maxim=S[i][j];
        }
    }
    printf("%d",maxim);
    return 0;
}