#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template <typename T>
using indexed_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
static mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define ll long long
#define pb push_back
#define ppb pop_back
#define pf push_front
#define ppf pop_front
#define eb emplace_back
#define ins insert
#define F fist
#define S second
constexpr int MAXN = 1e5;
const int LOG = __lg(MAXN)+1;
constexpr int INF = 1e9;
constexpr int MOD = 1e9+7;
constexpr double EPS = 1e-8;
/*
EJOI 2019, Day 2, problem A, 100p.
*/
int f(char f, char t){
if (f == 'X'){
return INF;
}
if (f == t){
return 0;
}
if (f == 'W'){
if (t == 'N'){
return 1;
} else if (t == 'E'){
return 2;
} else {
return 3;
}
} else if (f == 'N'){
if (t == 'W'){
return 3;
} else if (t == 'S'){
return 2;
} else {
return 1;
}
} else if (f == 'E'){
if(t == 'W'){
return 2;
} else if (t == 'S'){
return 1;
} else {
return 3;
}
} else{
if (t == 'W'){
return 1;
} else if (t == 'N'){
return 2;
} else {
return 3;
}
}
}
int n, m;
bool ok(int tx, int ty){
return 0 <= tx && tx < n && 0 <= ty && ty < m;
}
void solve(){
cin >> n >> m;
vector<string> g(n);
for(auto& x: g){
cin >> x;
}
vector<vector<int>> d(n, vector<int>(m, INF));
set<tuple<int, int, int>> q;
vector<int> dx = {1, -1, 0, 0};
vector<int> dy = {0, 0, 1, -1};
string v = "SNEW";
q.ins({d[0][0] = 0, 0, 0});
int dist, x, y;
while(!q.empty()){
tie(dist, x, y) = *q.begin();
q.erase(q.begin());
for(int k = 0; k < 4; k++){
int tx = x + dx[k], ty = y + dy[k];
if (ok(tx, ty)){
if(tx != n-1 && ty != m-1 && g[tx][ty] == 'X'){
continue;
}
if (dist + f(g[x][y], v[k]) < d[tx][ty]){
q.erase({d[tx][ty], tx, ty});
d[tx][ty] = dist + f(g[x][y], v[k]);
q.ins({d[tx][ty], tx, ty});
}
}
}
}
if (d[n-1][m-1] == INF){
cout << "-1\n";
} else{
cout << d[n-1][m-1] << '\n';
}
}
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
int t = 1;
// cin >> t;
for(int i = 1; i <= t; i++){
solve();
}
}
