#include <iostream>
#include <string.h>
#include <queue>
#include <limits.h>
#include <cstdio>
using namespace std;

struct Point
{
	int x;
	int y;
	Point(int x_,int y_):x(x_),y(y_){}
};

const int dx[] = {1,0,-1,0};
const int dy[] = {0,1,0,-1};

int main(void)
{
	while(1){
		int w,h;
		int field[105][105] = {};
		int costfield[105][105];
		Point gPoint(0,0);
		cin >> w >> h;

		for(int i=0;i<105;++i){
			for(int j=0;j<105;++j){
				costfield[i][j] = INT_MAX;
				if(i==0||j==0||i==h+3||j==w+3)
					costfield[i][j] = -1;
			}
		}

		if(w == 0 && h == 0)
			return 0;
		for(int y=1;y<=h+2;++y){
			for(int x=1;x<=w+2;++x){
				if(x==1 || y==1 || x==w+2 || y==h+2)
				{
					field[y][x] = '.';
				}
				else{
					scanf(" %c",&field[y][x]);
					if(field[y][x] == '&')
						gPoint = Point(x,y);
				}
			}
		}
		costfield[1][1] = 0;

		queue<Point> que;
		que.push(Point(1,1));
		while(!que.empty()){
			Point now = que.front();
			que.pop();
			for(int i=0;i<4;++i){
				Point next(now.x+dx[i],now.y+dy[i]);
				int c = costfield[now.y][now.x] + (field[now.y][now.x] == '.' && field[next.y][next.x] == '#' ? 1 : 0);
				if(c < costfield[next.y][next.x]){
					costfield[next.y][next.x] = c;
					que.push(next);
				}
			}
		}
		cout << costfield[gPoint.y][gPoint.x] << endl;
	}
	return 0;
}