#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll n,m;
map<pair<char,char>,ll>moves;
map<char,ll>ii;;
map<char,ll>jj;
vector<char>v={'E','S','W','N'};
const ll inf = 1e18;
char a[600][600];
ll dis[600][600];
int main(){
moves[{'E','E'}]=0;
moves[{'E','S'}]=1;
moves[{'E','W'}]=2;
moves[{'E','N'}]=3;
moves[{'S','S'}]=0;
moves[{'S','W'}]=1;
moves[{'S','N'}]=2;
moves[{'S','E'}]=3;
moves[{'W','W'}]=0;
moves[{'W','N'}]=1;
moves[{'W','E'}]=2;
moves[{'W','S'}]=3;
moves[{'N','N'}]=0;
moves[{'N','E'}]=1;
moves[{'N','S'}]=2;
moves[{'N','W'}]=3;
ii['S']=1;
jj['S']=0;
ii['N']=-1;
jj['N']=0;
ii['W']=0;
jj['W']=-1;
ii['E']=0;
jj['E']=1;
cin>>n>>m;
for(ll i=1;i<=n;i++){
for(ll j=1;j<=m;j++){
cin>>a[i][j];
dis[i][j]=inf;
}
}
priority_queue<pair<ll,pair<ll,ll>>>q;
for(auto it:v){
ll fi = 1+ii[it];
ll fj = 1+jj[it];
if(fi<1 || fi>n || fj<0 || fj>m){
continue;
}
if(dis[fi][fj]>0+moves[{a[1][1],it}]){
dis[fi][fj]=0+moves[{a[1][1],it}];
q.push({dis[fi][fj],{fi,fj}});
}
}
while(!q.empty()){
ll i = q.top().second.first;
ll j = q.top().second.second;
ll k = q.top().first;
q.pop();
if(dis[i][j]<k || a[i][j]=='X'){
continue;
}
for(auto it:v){
ll fi = i+ii[it];
ll fj = j+jj[it];
if(fi<1 || fi>n || fj<0 || fj>m){
continue;
}
if(dis[fi][fj]>k+moves[{a[i][j],it}]){
dis[fi][fj]=k+moves[{a[i][j],it}];
q.push({dis[fi][fj],{fi,fj}});
}
}
}
if(dis[n][m]!=inf){
cout<<dis[n][m];
}else{
cout<<-1;
}
}
