#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> ii;
const int nx = 505, INF = 2e9;
int m, n, sdist[nx][nx] = {0}, rotcost[4] = {0, 1, 2, 3};
ii dir[4] = {{-1, 0}, {0, 1}, {1, 0}, {0, -1}};
string grid[nx];
bool visited[nx][nx] = {false};
priority_queue<pair<int, ii> , vector<pair<int, ii>>, greater<pair<int, ii>>> pq;
int main(){
cin.tie(NULL)->sync_with_stdio(false);
cin >> m >> n;
for(int i=0; i<m; i++) cin >> grid[i];
for(int i=0; i<m; i++){
for(int j=0; j<n; j++){
sdist[i][j] = INF;
}
} sdist[0][0] = 0;
pq.push({0, {0, 0}});
while(!pq.empty()){
auto [rot, pnt] = pq.top();
// cout << rot << ' ' << pnt.first << ' ' << pnt.second << "\n";
pq.pop();
if(visited[pnt.first][pnt.second]) continue;
visited[pnt.first][pnt.second] = true;
char room = grid[pnt.first][pnt.second];
if(room=='X') continue;
for(int i=0; i<4; i++){
// cout << "i = " << i << "\n";
int ty = pnt.first+dir[i].first, tx = pnt.second+dir[i].second;
if(ty<0 || ty>=m || tx<0 || tx>=n || visited[ty][tx]) continue;
if(room=='N'){
if(sdist[ty][tx]>rot+(i%4)){
sdist[ty][tx] = rot+(i%4);
pq.push({sdist[ty][tx], {ty, tx}});
// cout << "roomN push\n";
}
} else if(room=='W'){
if(sdist[ty][tx]>rot+((i+1)%4)){
sdist[ty][tx] = rot+((i+1)%4);
pq.push({sdist[ty][tx], {ty, tx}});
// cout << "roomW push\n";
}
} else if(room=='S'){
if(sdist[ty][tx]>rot+((i+2)%4)){
sdist[ty][tx] = rot+((i+2)%4);
pq.push({sdist[ty][tx], {ty, tx}});
// cout << "roomS push\n";
}
} else{
if(sdist[ty][tx]>rot+((i+3)%4)){
sdist[ty][tx] = rot+((i+3)%4);
pq.push({sdist[ty][tx], {ty, tx}});
// cout << "roomE push\n";
}
}
}
}
cout << (sdist[m-1][n-1]==INF ? -1 : sdist[m-1][n-1]);
return 0;
}
