#include<bits/stdc++.h>
using namespace std;
#define p push
const int maxn = 507;
int kr[4]={-1,0,1,0};
int ks[4]={0,1,0,-1};
int n,m;
char c;
int sve[maxn][maxn];
int dji[maxn][maxn];
priority_queue<pair<int,pair<int,int>> ,vector<pair<int,pair<int,int>>> , greater<pair<int,pair<int,int>>>> q;
int main(){
	cin>>n>>m;
	for(int i = 0; i<n; i++){
		for(int j = 0; j<m; j++){
			cin>>c;
			if(c=='X'){
				sve[i][j]=-1;
			}
			else if(c=='N'){
				sve[i][j]=0;
			}
			else if(c=='E'){
				sve[i][j]=1;
			}
			else if(c=='S'){
				sve[i][j]=2;
			}
			else if(c=='W'){
				sve[i][j]=3;
			}
		}
	}
	if(sve[0][0]==-1){
		cout<<-1;
		return 0;
	}
	sve[n-1][m-1]=-2;
	q.p({0,{0,0}});
	pair<int,pair<int,int>> tr;
	bool ch = true;
	while(!q.empty() and ch){
		tr=q.top();
		dji[tr.second.first][tr.second.second]=1;
		if(tr.second.first==n-1 and tr.second.second==m-1){
			cout<<tr.first;
			ch=false;
			break;
		}
		int pr = sve[tr.second.first][tr.second.second];
		//cout<<tr.first<<"     "<<tr.second.first<<' '<<tr.second.second<<"    "<<pr<<endl;
		q.pop();
		for(int i = sve[tr.second.first][tr.second.second]; i<sve[tr.second.first][tr.second.second]+4; i++){
			int r = tr.second.first +kr[i%4];
			int s = tr.second.second + ks[i%4];
			if(r>n-1 or s>m-1 or r<0 or s<0 or dji[r][s]!=0 or sve[r][s]==-1){
				continue;
			}
			else{
				//cout<<i<<"  "<<r<<' '<<s<<endl;
				q.p({tr.first+(i-pr),{r,s}});
			}
		}
	}
	if(ch) cout<<-1;
	
	
	
}