#include<bits/stdc++.h>
using namespace std;

#define REP(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) REP(i,0,n)

#define mygc(c) (c)=getchar_unlocked()
#define mypc(c) putchar_unlocked(c)

#define ll long long
#define ull unsigned ll

void reader(int *x){int k,m=0;*x=0;for(;;){mygc(k);if(k=='-'){m=1;break;}if('0'<=k&&k<='9'){*x=k-'0';break;}}for(;;){mygc(k);if(k<'0'||k>'9')break;*x=(*x)*10+k-'0';}if(m)(*x)=-(*x);}
void reader(ll *x){int k,m=0;*x=0;for(;;){mygc(k);if(k=='-'){m=1;break;}if('0'<=k&&k<='9'){*x=k-'0';break;}}for(;;){mygc(k);if(k<'0'||k>'9')break;*x=(*x)*10+k-'0';}if(m)(*x)=-(*x);}
void reader(double *x){scanf("%lf",x);}
int reader(char c[]){int i,s=0;for(;;){mygc(i);if(i!=' '&&i!='\n'&&i!='\r'&&i!='\t'&&i!=EOF) break;}c[s++]=i;for(;;){mygc(i);if(i==' '||i=='\n'||i=='\r'||i=='\t'||i==EOF) break;c[s++]=i;}c[s]='\0';return s;}
template <class T, class S> void reader(T *x, S *y){reader(x);reader(y);}
template <class T, class S, class U> void reader(T *x, S *y, U *z){reader(x);reader(y);reader(z);}
template <class T, class S, class U, class V> void reader(T *x, S *y, U *z, V *w){reader(x);reader(y);reader(z);reader(w);}

void writer(int x, char c){int s=0,m=0;char f[10];if(x<0)m=1,x=-x;while(x)f[s++]=x%10,x/=10;if(!s)f[s++]=0;if(m)mypc('-');while(s--)mypc(f[s]+'0');mypc(c);}
void writer(ll x, char c){int s=0,m=0;char f[20];if(x<0)m=1,x=-x;while(x)f[s++]=x%10,x/=10;if(!s)f[s++]=0;if(m)mypc('-');while(s--)mypc(f[s]+'0');mypc(c);}
void writer(double x, char c){printf("%.15f",x);mypc(c);}
void writer(const char c[]){int i;for(i=0;c[i]!='\0';i++)mypc(c[i]);}
void writer(const char x[], char c){int i;for(i=0;x[i]!='\0';i++)mypc(x[i]);mypc(c);}
template<class T> void writerLn(T x){writer(x,'\n');}
template<class T, class S> void writerLn(T x, S y){writer(x,' ');writer(y,'\n');}
template<class T, class S, class U> void writerLn(T x, S y, U z){writer(x,' ');writer(y,' ');writer(z,'\n');}
template<class T> void writerArr(T x[], int n){int i;if(!n){mypc('\n');return;}rep(i,n-1)writer(x[i],' ');writer(x[n-1],'\n');}

char memarr[17000000]; void *mem = memarr;
#define MD 1000000007

void gridGetDistCost01(int X, int Y, int *cost, int sx, int sy, int *res, void *mem, int d=4){int i,j,k,x,y,XY=X*Y,s[8]={-1,1,0,0,-1,1,-1,1},t[8]={0,0,-1,1,-1,-1,1,1},*q=(int*)mem,l,r;l=r=X*Y+1;q[r++]=sx*Y+sy;rep(i,XY)res[i]=-1;res[sx*Y+sy]=0;while(l!=r){k=q[l++];sx=k/Y;sy=k%Y;rep(i,d){x=sx+s[i];y=sy+t[i];j=x*Y+y;if(x<0||x>=X||y<0||y>=Y||cost[j]==-1)continue;if(res[j]==-1){res[j]=res[k]+cost[j];if(cost[j]==0)q[--l]=j;else q[r++]=j;}}}}

int X, Y;
char mp[222][222];

int cost[10000], dist[10000];

void nul(int a, int b, char s, char t){
  if(a < 0 || b < 0 || a >= X || b >= Y) return;
  if(mp[a][b]!=s) return;
  mp[a][b] = t;
  nul(a-1, b, s, t);
  nul(a+1, b, s, t);
  nul(a, b-1, s, t);
  nul(a, b+1, s, t);
}

int main(){
  int i, j, k;
  int si, sj, ei, ej;
  int fg = 0;

  reader(&Y,&X);
  rep(i,X) reader(mp[i]);

  rep(i,X) rep(j,Y) if(mp[i][j]=='.'){
    nul(i, j, '.', '1'+fg);
    fg++;
  }

  rep(i,X) rep(j,Y){
    cost[i*Y+j] = 0;
    if(mp[i][j]=='#') cost[i*Y+j] = 1;
  }

  rep(i,X) rep(j,Y){
    if(mp[i][j]=='1'){
      si = i;
      sj = j;
    }
    if(mp[i][j]=='2'){
      ei = i;
      ej = j;
    }
  }
  gridGetDistCost01(X,Y,cost,si,sj,dist,mem);
  writerLn(dist[ei*Y+ej]);

  return 0;
}