#include "bits/stdc++.h"
using namespace std;
#define mod 998244353
#define ll long long
#define ff first
#define ss second
#define pb push_back
#define N 24
#define maxn 505
ll n,m;
map<char,ll> cost;
string s[maxn];
ll a[maxn][maxn];
void solve(){
cin>>n>>m;
for(ll i=0; i<n; i++) cin>>s[i];
for(ll j=0; j<n; j++){
for(ll i=0; i<m; i++){
if(s[j][i]=='E') s[j][i]='R';
else if(s[j][i]=='N') s[j][i]='U';
else if(s[j][i]=='S') s[j][i]='D';
else if(s[j][i]=='W') s[j][i]='L';
}
}
for(ll i=0; i<n; i++) for(ll j=0; j<m; j++) a[i][j]=1e15;
cost['R']=1;
cost['U']=2;
cost['L']=3;
cost['D']=4;
a[n-1][m-1]=0;
priority_queue<pair<ll,pair<ll,ll> >,vector<pair<ll,pair<ll,ll> > >,greater<pair<ll,pair<ll,ll> > > > pq;
pq.push({0,{n-1,m-1}});
while(!pq.empty()){
pair<ll,pair<ll,ll> > p=pq.top();
// cout<<p.ff<<' ';
pq.pop();
ll x=p.ss.ff,y=p.ss.ss;
if(x>0 and (a[x][y]+(cost[s[x-1][y]]-cost['D']+4)%4)<a[x-1][y] and s[x-1][y]!='X'){
a[x-1][y]=a[x][y]+(cost[s[x-1][y]]-cost['D']+4)%4;
pq.push({a[x-1][y],{x-1,y}});
}
if(y>0 and (a[x][y]+(cost[s[x][y-1]]-cost['R']+4)%4)<a[x][y-1] and s[x][y-1]!='X'){
a[x][y-1]=a[x][y]+(cost[s[x][y-1]]-cost['R']+4)%4;
pq.push({a[x][y-1],{x,y-1}});
}
if(x+1<n and (a[x][y]+(cost[s[x+1][y]]-cost['U']+4)%4)<a[x+1][y] and s[x+1][y]!='X'){
a[x+1][y]=a[x][y]+(cost[s[x+1][y]]-cost['U']+4)%4;
pq.push({a[x+1][y],{x+1,y}});
}
if(y+1<m and (a[x][y]+(cost[s[x][y+1]]-cost['L']+4)%4)<a[x][y+1] and s[x][y+1]!='X'){
a[x][y+1]=a[x][y]+(cost[s[x][y+1]]-cost['L']+4)%4;
pq.push({a[x][y+1],{x,y+1}});
}
}
if(a[0][0]==1e15) cout<<-1;
else cout<<a[0][0];
}
int main(){
// freopen("in.txt","w",stdout);
// freopen("out.txt","r",stdin);
ios_base::sync_with_stdio(0); cin.tie(0);
ll t=1;
// cin>>t;
while(t--) solve();
}
