#include <cstdio>

#include <algorithm>

#include <queue>

#define MAX 1010

#define INF 987654321

using namespace std;

struct Point {

int r, c, passed;

};

int n, m;

int result = 100000;

int map[MAX][MAX];

int dist[MAX][MAX][2];

int dr[] = {0 ,0, 1, -1};

int dc[] = {1, -1, 0, 0};

queue<Point> q;

void bfs() {

while(!q.empty()) {

int r = q.front().r;

int c = q.front().c;

int passed = q.front().passed;

q.pop();

for(int k=0; k<4; k++) {

int nr = r + dr[k];

int nc = c + dc[k];

if(nr < 0 || nr > n || nc < 0 || nc > m) continue;

// 다음곳 방문 여부

if(dist[nr][nc][passed] > dist[r][c][passed]+1) {

// 벽이고, 아직 벽을 부수지 않았다면

if(map[nr][nc] == 1 && passed == 0) {

dist[nr][nc][1] = dist[r][c][0] + 1;

q.push(Point{nr,nc,1});

} else if(map[nr][nc] == 0) {

q.push(Point{nr,nc,passed});

dist[nr][nc][passed] = dist[r][c][passed] +1;

}

}

}

}

}

int main() {

scanf("%d %d", &n, &m);

for(int i=0; i<n; i++){

for(int j=0; j<m; j++) {

scanf("%1d", &map[i][j]);

dist[i][j][0] = dist[i][j][1] = INF;

}

}

q.push(Point{0,0,0});

dist[0][0][0] = dist[0][0][1] = 1;

bfs();

result = dist[n-1][m-1][0];

if(result > dist[n-1][m-1][1]) result = dist[n-1][m-1][1];

if(result == INF) printf("-1\n");

else printf("%d\n", result);

return 0;

}