#include <cstdio>
#include <stdio.h>
#include <stdbool.h>
#include <iostream>
#include <map>
#include <vector>
#include <climits>
#include <stack>
#include <string>
#include <queue>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cmath>
#include <cctype>
#include <bitset>
#include <iomanip>
#include <cstring>
#include <numeric>
#include <cassert>
using namespace std;
#define int long long
#define pii pair<int, int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second
int dy[4]={0, 1, 0, -1};
int dx[4]={-1, 0, 1, 0};
int32_t main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n, m;
cin>>n>>m;
map<char, int> val;
val['N']=0;
val['E']=1;
val['S']=2;
val['W']=3;
vector<string> graph(n);
vector<vector<int> > dist(n, vector<int>(m, LLONG_MAX/2));
for (int i=0; i<n; ++i)cin>>graph[i];
priority_queue<pair<int, pii>, vector<pair<int, pii> >, greater<pair<int, pii> > > pq;
pq.push(mp(0, mp(0, 0)));
while (pq.size()){
int d=pq.top().fi, x=pq.top().se.fi, y=pq.top().se.se;
pq.pop();
if (d>=dist[x][y])continue;
dist[x][y]=d;
for (int i=0; i<4; ++i){
int nx=x+dx[i], ny=y+dy[i];
if (nx<0||ny<0||nx>=n||ny>=m||graph[x][y]=='X')continue;
pq.push(mp(d+(i-val[graph[x][y]]+4)%4, mp(nx, ny)));
}
}
cout<<(dist[n-1][m-1]==LLONG_MAX/2?-1:dist[n-1][m-1]);
}
