#include <bits/stdc++.h>
using namespace std;
vector<int> g[250000], s[250000];
char mp[500][500];
int tav[250000];
unordered_map<char, array<int, 4>> dirtos = {
{'E', {0, 1, 2, 3}},
{'S', {3, 0, 1, 2}},
{'W', {2, 3, 0, 1}},
{'N', {1, 2, 3, 0}}
};
int main(){
int n, m; cin>>n>>m;
for(int i = 0; i < n; i++){
for(int j = 0; j < m; j++){
char c; cin>>c;
mp[i][j] = c;
if(c=='X')continue;
int nodeindex = i*500+j;
if(j < m-1 && mp[i][j+1] != 'X'){
g[nodeindex].push_back(nodeindex+1);
s[nodeindex].push_back(dirtos[c][0]);
}
if(i < n-1 && mp[i+1][j] != 'X'){
g[nodeindex].push_back(nodeindex+500);
s[nodeindex].push_back(dirtos[c][1]);
}
if(j > 0 && mp[i][j-1] != 'X'){
g[nodeindex].push_back(nodeindex-1);
s[nodeindex].push_back(dirtos[c][2]);
}
if(i > 0 && mp[i-1][j] != 'X'){
g[nodeindex].push_back(nodeindex-500);
s[nodeindex].push_back(dirtos[c][3]);
}
}
}
priority_queue<pair<int,int>> q;
for(int&i:tav)i=INT_MAX;
tav[0] = 0;
q.push({0, 0});
while(!q.empty()){
int v = q.top().second;
int t = -q.top().first;
q.pop();
if(tav[v] < t)continue;
for(int i = 0; i < g[v].size(); i++){
int k = g[v][i];
int su = s[v][i];
if(t + su < tav[k]){
tav[k] = t+su;
q.push({-tav[k], k});
}
}
}
if(tav[(n-1)*500+(m-1)] == INT_MAX)cout<<-1;
else cout<<tav[(n-1)*500+(m-1)];
return 0;
}
