#include <cstdio>
#include <algorithm>
#include <queue>
#include <cmath>

#define MAXN 1005
using namespace std;

int N, M;
bool flag[MAXN][MAXN][2];
int maze[MAXN][MAXN];
int dx[] = {1,-1,0,0};
int dy[] = {0,0,1,-1};

struct state {
    int dist;
    int x;
    int y;
    bool smell;
    int dir;

    state(int dist, int x, int y, bool smell, int dir) :
        dist(dist), x(x), y(y), smell(smell), dir(dir) {
    }

    void dsmell(bool scent){
        smell = scent;
    }
};

queue<state> q;

 bool able(int r, int c, bool smell){
    if(r>=0 && r<N && c>=0 && c<M){
        if(maze[r][c] == 0) return false;
        else if(maze[r][c] == 3) return smell;
        else return true;
    }
    return false;
}

int main(){
    freopen("dream.in","r",stdin);
    freopen("dream.out", "w", stdout);

    scanf("%d %d", &N, &M);

    for(int i = 0; i<N; i++){
        for(int j = 0; j<M; j++){
            scanf("%d", &maze[i][j]);
        }
    }

    q.push(state(0,0,0,false, 0));

    while(!q.empty()){
        state node = q.front();
        q.pop();

        if(node.x == N-1 && node.y == M-1){
            printf("%d\n", node.dist);
            return 0;
        }

        if(!flag[node.x][node.y][node.smell ? 0 : 1]){
            flag[node.x][node.y][node.smell ? 0 : 1] = true;

            if(maze[node.x][node.y] == 4 && able(node.x+dx[node.dir], node.y+dy[node.dir], node.smell)){
                q.push(state(node.dist+1, node.x+dx[node.dir], node.y+dy[node.dir], node.smell, node.dir));
                continue;
            }

            else{
                for(int i=0; i<4; i++){
                    if(!able(node.x+dx[i], node.y+dy[i], node.smell)) continue;

                    state child = state(node.dist+1, node.x+dx[i], node.y+dy[i], node.smell, i);

                    if(maze[child.x][child.y] == 2) child.dsmell(true);
                    if(maze[child.x][child.y] == 4) child.dsmell(false);

                    q.push(child);
                }
            }
        }
    }

    printf("%d\n",-1);

    return 0;
}