#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];
int dir[N][N];
struct Point
{
int x,y;
};
bool cmp(pair<int,Point> a, pair<int,Point> b)
{
return a.first>b.first;
}
vector<pair<Point,int>> g[N][N];
int dist[N][N];
signed main()
{
ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
int n,m;
cin>>n>>m;
char ch;
for(int i=1;i<=n;++i) for(int j=1;j<=m;++j) cin>>v[i][j];
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)
{
if(v[i][j]=='X') continue;
for(int d=0;d<4;++d)
{
int ni=i+dx[d],nj=j+dy[d];
if(ni<1||ni>n||nj<1||nj>m) continue;
g[i][j].pb({{ni,nj},(d-dir[i][j]+4)%4});
}
}
priority_queue<pair<int,pair<int,int>>,vector<pair<int,pair<int,int>>>,greater<pair<int,pair<int,int>>>> pq;
for(int i=1;i<=n;++i) for(int j=1;j<=m;++j) dist[i][j]=1e18;
dist[1][1]=0;
pq.push({0,{1,1}});
while(!pq.empty())
{
int x=pq.top().second.first,y=pq.top().second.second;
pq.pop();
for(auto p:g[x][y])
{
int nx=p.first.x,ny=p.first.y;
if(dist[nx][ny]<=dist[x][y]+p.second) continue;
dist[nx][ny]=dist[x][y]+p.second;
pq.push({dist[nx][ny],{nx,ny}});
}
}
cout<<(dist[n][m]==1e18 ? -1:dist[n][m]);
}
