#include <bits/stdc++.h>
#define pb push_back
#define int long long
using namespace std;
const int N=5e2+5;
int dx[]={-1,0,1,0};
int dy[]={0,1,0,-1};
char v[N][N];
bool vis[N][N];
bool dfs(vector<vector<int>> dir, int x=1, int y=1)
{
if(x<1||x>3||y<1||y>3) return 0;
if(vis[x][y]) return 0;
vis[x][y]=1;
if(x==3&&y==3) return 1;
if(v[x][y]=='X') return 0;
return dfs(dir,x+dx[dir[x][y]],y+dy[dir[x][y]]);
}
int bkt(int x, int y, int cost, vector<vector<int>> dir)
{
//cout<<x<<" "<<y<<" ";
//if(x>3||y>3) return 1e18;
if(x==4)
{
for(int i=1;i<=3;++i) for(int j=1;j<=3;++j) vis[i][j]=0,dir[i][j]%=4;
/*for(int i=1;i<=3;++i)
{
for(int j=1;j<=3;++j) cout<<dir[i][j]<<" ";
cout<<'\n';
}
cout<<'\n';*/
if(dfs(dir)) return cost;
return 1e18;
}
assert(1<=x&&x<=3&&1<=y&&y<=3);
int nx=x,ny=y+1;
if(ny==4) ++nx,ny=1;
if(v[x][y]=='X') return bkt(nx,ny,cost,dir);
int mn=1e18;
mn=min(mn,bkt(nx,ny,cost,dir));
++dir[x][y];
mn=min(mn,bkt(nx,ny,++cost,dir));
++dir[x][y];
mn=min(mn,bkt(nx,ny,++cost,dir));
++dir[x][y];
mn=min(mn,bkt(nx,ny,++cost,dir));
return mn;
}
signed main()
{
ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
int n,m;
cin>>n>>m;
for(int i=1;i<=n;++i) for(int j=1;j<=m;++j) cin>>v[i][j];
vector<vector<int>> dir(4,vector<int>(4));
for(int i=1;i<=n;++i) for(int j=1;j<=m;++j)
{
if(v[i][j]=='X') continue;
if(v[i][j]=='N') dir[i][j]=0;
if(v[i][j]=='E') dir[i][j]=1;
if(v[i][j]=='S') dir[i][j]=2;
if(v[i][j]=='W') dir[i][j]=3;
}
/*for(int i=1;i<=n;++i)
{
for(int j=1;j<=m;++j) cout<<dir[i][j]<<" ";
cout<<'\n';
}
cout<<'\n';*/
//return 0;
int ans=bkt(1,1,0,dir);
cout<<(ans==1e18 ? -1:ans);
}
