#include<bits/stdc++.h>
using namespace std;
int f[2][1000],dx[4]={0,1,-1,0},dy[4]={1,0,0,-1},ans=100001,n,c,m[1001][1001];
char s[100][100];
int bfs(int x,int y,int r){
int l=r;
if(x==n&&y==c&&l<ans){
ans=r;
f[0][r]=x;
f[1][r]=y;
return 1;
}
if(r>ans)
return 2;
bool q=0;
for(int i=0;i<=3;i++){
if((x+dx[i])<=n&&(y+dy[i])<=c&&(x+dx[i])>0&&(y+dy[i])>0&&s[x+dx[i]][y+dy[i]]!='*'&&m[x+dx[i]][y+dy[i]]==1){
m[x+dx[i]][y+dy[i]]=0;
if(bfs(x+dx[i],y+dy[i],l+1)==1){
q=1;
f[0][r]=x;
f[1][r]=y;
}
m[x+dx[i]][y+dy[i]]=1;
}
}
if(q){
return 1;
}
return 2;
}
int main(){
int x=1,y=1;
cin>>n>>c;
for(int i=1;i<=n;i++){
for(int j=1;j<=c;j++){
cin>>s[i][j];
m[i][j]=1;
}
}
if(bfs(x,y,1)==2){
cout<<-1<<endl;
}
else{
for(int i=1;i<=ans;i++){
cout<<f[0][i]<<' '<<f[1][i]<<endl;
}
}
return 0;
}