#include<iostream>
#include<iomanip>
#include<string>
#include<queue>
#include<algorithm>

#define REP(i,a,n) for(int i=(a);i<(n);++i)

#define INV (-1)
#define N 102
#define INFTY (1<<30)
#define PLANE 2
#define MOAT 1

using namespace std;

int n,m;
int map[N][N];
int M[N][N];

bool inline inRange(int t, int min, int max){
	return min <= t && t < max;
}

void dfs(int i, int j, int now){
	const int ci[] = {-1,0,1,0};
	const int cj[] = {0,1,0,-1};

	if( M[i][j] != now )
		return ;

	for(int k = 0; k < sizeof(ci)/sizeof(*ci); ++k){
		int ti = i + ci[k];
		int tj = j + cj[k];
		if( inRange( ti, 1, m+1 ) && inRange( tj, 1, n+1 ) ){
			if( map[i][j] == MOAT && map[ti][tj] == PLANE ){
				M[ti][tj] = min( M[ti][tj], now + 1 );
				continue;
			}
			if( M[ti][tj] == now ){
				continue;
			}
			M[ti][tj] = now;
			dfs( ti, tj, now );
		}
	}
	return ;
}
void ResetMap(){
	REP(i,0,N)REP(j,0,N)
	{
		map[i][j] = PLANE;
		M[i][j] = INFTY;
	}
}
void PrintMap(){
	REP(i,1,m+1){
		REP(j,1,n+1){
			cout << setw(3) << M[i][j];
		}
		cout << endl;
	}
	cout << endl;
}
bool Completed(int *ans){
	REP(i,1,m+1){
		if( M[i][1] < INFTY ){
			*ans = M[i][1];
			return true;
		}
		if( M[i][n] < INFTY ){
			*ans = M[i][n];
			return true;
		}
	}
	REP(j,1,n+1){
		if( M[1][j] < INFTY ){
			*ans = M[1][j];
			return true;
		}
		if( M[m][j] < INFTY ){
			*ans = M[m][j];
			return true;
		}
	}

	return false;
}

int main(){
	while(true){
		int now = 0;
		int ans = 1<<21;
		int si;
		int sj;
		
		cin>>n>>m;
		if( m==0&&n==0 )break;
		
		ResetMap();
		
		REP(i,1,m+1){
			string s;
			cin>>s;
			REP(j,1,n+1){
				if( s[j-1] == '&' ){
					si = i;
					sj = j;
					M[si][sj] = 0;
				}else if( s[j-1] == '#' ){
					map[i][j] = MOAT;
				}
			}
		}

		while( true ){
			REP(i,1,m+1){
				REP(j,1,n+1){
					dfs( i, j, now );		
				}
			}
			if( Completed(&ans) )
				break;
			else{
				++now;
			}
		}
		cout << ans << endl;
	}
	return 0;
}