#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<cassert>
#include<iostream>
#include<sstream>
#include<string>
#include<vector>
#include<queue>
#include<set>
#include<map>
#include<utility>
#include<numeric>
#include<algorithm>
#include<bitset>
#include<complex>

using namespace std;

typedef long long Int;
typedef vector<int> vint;
typedef pair<int,int> pint;
#define mp make_pair

template<class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cout << *i << " "; cout << endl; }
template<class T> void chmin(T &t, T f) { if (t > f) t = f; }
template<class T> void chmax(T &t, T f) { if (t < f) t = f; }
int in() { int x; scanf("%d", &x); return x; }

char mt[110][110];
int res[110][110];

int main() {
	int n,m;
	while(n=in(),m=in()){
		int i,j;
		for(i=0;i<m;i++){
			for(j=0;j<n;j++){
				cin>>mt[i][j];
				res[i][j]=1000000000;
			}
		}
		int k;
		for(k=0;k<n*m;k++){
			for(i=0;i<m;i++){
				for(j=0;j<n;j++){
					if(i==0||j==0||i==m-1||j==n-1){
						if(mt[i][j]=='#')res[i][j]=1;
						else res[i][j]=0;
					}else{
						int p;
						int xx[]={1,-1,0,0};
						int yy[]={0,0,1,-1};
						for(p=0;p<4;p++){
							if(0<=i+yy[p]&&i+yy[p]<m&&0<=j+xx[p]&&j+xx[p]<n){
								if(mt[i][j]=='#')chmin(res[i][j],res[i+yy[p]][j+xx[p]]+1);
								else chmin(res[i][j],res[i+yy[p]][j+xx[p]]);
							}
						}
					}
				}
			}
		}
		for(i=0;i<m;i++){
			for(j=0;j<n;j++){
				if(mt[i][j]=='&')cout<<res[i][j]<<endl;
//cout<<res[i][j];
			}
//cout<<endl;
		}
		
	}
	return 0;
}