#include <iostream>
#include <queue>
#include <vector>
#include <algorithm>
#include <cstring>

using namespace std;

struct node{
int x;
int y;
int distance;
node(){

}
node(int _x, int _y, int _distance){
x=_x;
y=_y;
distance=_distance;
}
bool operator <(const node& temp)const{
return distance<temp.distance;
}
};


int main()
{
int n, m;
cin>>n;
cin>>m;
char matrica[n][m];
bool visited[n][m];
int sy;
int sx;
int ex;
int ey;
int distance[n][m];
vector<pair<int, int>>v;
priority_queue<node>pq;
queue<int>q;
for(int y=0; y<n; y++){
    for(int y1=0; y1<m; y1++){
        visited[y][y1]=false;
    }
}
for(int x=0; x<n; x++){
    for(int x1=0; x1<m; x1++){
        cin>>matrica[x][x1];
      if(matrica[x][x1]=='G'){
        q.push(x);
        q.push(x1);
        q.push(0);
      }
        if(matrica[x][x1]=='R'){
        sx=x;
        sy=x1;
      }
      if(matrica[x][x1]=='Z'){
        ex=x;
        ey=x1;
      }
}
}
for(int h=0; h<n; h++){
    for(int h1=0; h1<m; h1++){
        distance[h][h1]=-1;
    }
}

    int dx[]={1,0,-1,0};
    int dy[]={0,1,0,-1};
    while(!q.empty()){
    int cx=q.front();
    q.pop();
    int cy=q.front();
    q.pop();
    int brojac=q.front();
    q.pop();
    if(matrica[cx][cy]=='G'){
        distance[cx][cy]=0;
        visited[cx][cy]=true;
    }
    for(int y=0; y<4; y++){
        int tx=cx+dx[y];
        int ty=cy+dy[y];
    if((tx>=0)and(ty>=0)and(tx<n)and(ty<m)and(visited[tx][ty]==false)and(matrica[tx][ty]!='*')){
       q.push(tx);
       q.push(ty);
       visited[tx][ty]=true;
       distance[tx][ty]=brojac+1;
       q.push(brojac+1);
       }
    }
    }


    for(int d=0; d<n; d++){
        for(int d1=0; d1<m; d1++){
            visited[d][d1]=false;
            cout << distance[d][d1] << " " ;
        }
        cout << endl;
    }

    pq.push(node(sx, sy, distance[sx][sy]));
    while(!pq.empty()){
    node c=pq.top();
    pq.pop();
    if((c.x==ex)and(c.y==ey)){
        cout<<c.distance;
        return 0;
    }
    for(int d2=0; d2<4; d2++){
        int tx=c.x+dx[d2];
        int ty=c.y+dy[d2];
        if((ty>=0)and(tx>=0)and(tx<n)and(ty<m)and(visited[tx][ty]==false)and(matrica[tx][ty]='.')){
          pq.push(node(tx, ty, min(distance[tx][ty], c.distance)));
          visited[tx][ty]=true;
        }
    }
    }
    return 0;
}
/*
 4 3 2 3 4 3 2 3 4
 3 2 1 2 3 2 1 2 3
 2 1 0 1 2 1 0 1 2
 1 2 1 2 2 2 1 2 3
 0 1 2 2 1 2 2 3 4
 1 2 2 1 0 1 2 3 4
 2 3 3 -1 -1 2 3 4 5
 3 4 4 5 4 3 4 5 6
 
 */