#include<iostream>
using namespace std;
int n,m,a[11][11],minn=99999;
void dfs(int x,int y,int sm,int sum){
	if(a[x][y]==0)return;
	if(sm==0){
		return;
	}
	if(a[x][y]==4)sm=6;
	if(a[x][y]==3){
		if(sum<minn)minn=sum;
		sum=0;
		return;
	}
	dfs(x-1,y,sm-1,sum+1);
	dfs(x,y-1,sm-1,sum+1);
	dfs(x+1,y,sm-1,sum+1);
	dfs(x,y+1,sm-1,sum+1);
}
int main(){
	int nn,mm;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			cin>>a[i][j];
			if(a[i][j]==2){
				nn=i;
				mm=j;
			}
		}
	}
	dfs(nn,mm,6,0);
	if(minn==99999){
		cout<<-1<<endl;
		return 0;
	}
	cout<<minn<<endl;
	return 0;
}

MLE，36分