#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 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, 12p.
*/
int f(char f, char t){
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;
vector<string> grid;
vector<vector<bool>> vis;
int solve(int x, int y){
if (x == n-1 && y == m-1){
return 0;
}
if (grid[x][y] == 'X'){
return INF;
}
vis[x][y] = true;
static vector<int> dx = {1, -1, 0, 0};
static vector<int> dy = {0, 0, -1, 1};
static string v = "SNWE";
int res = INF;
for (int k = 0; k < 4; k++){
int tx = x + dx[k], ty = y + dy[k];
if(0 <= tx && tx < n && 0 <= ty && ty < m && !vis[tx][ty]){
res = min(res, f(grid[x][y], v[k]) + solve(tx, ty));
}
}
vis[x][y] = false;
return res;
}
void solve(){
cin >> n >> m;
grid.resize(n);
vis.assign(n, vector<bool>(m, 0));
for(auto& x: grid){
cin >> x;
}
int res = solve(0, 0);
if (res == INF){
cout << "-1";
} else{
cout << res;
}
cout << '\n';
}
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
int t = 1;
// cin >> t;
for(int i = 1; i <= t; i++){
solve();
}
}
