#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll gcd(ll a, ll b){return __gcd(a, b);}
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ll mask){return __builtin_popcountll(mask);}
int ctz(ll mask){return __builtin_ctzll(mask);}
int logOf(ll mask){return __lg(mask);}
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if (a < b) {a = b; return true;}
return false;
}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if (a > b) {a = b; return true;}
return false;
}
template <class T>
void printArr(T& container, string separator = " ", string finish = "\n"){
for(auto item: container) cout << item << separator;
cout << finish;
}
template <class T>
void remove_dup(vector<T> &a){
sort(ALL(a));
a.resize(unique(ALL(a)) - a.begin());
}
const int INF = 1e9 + 69;
int dx[] = {0, 1, 0, -1};
int dy[] = {1, 0, -1, 0};
int convert(char c){
if (c == 'E') return 0;
if (c == 'S') return 1;
if (c == 'W') return 2;
if (c == 'N') return 3;
return 4;
}
char convert_back(int c){
if (c == 0) return 'E';
if (c == 1) return 'S';
if (c == 2) return 'W';
return 'N';
}
void solve(){
int n, m; cin >> n >> m;
vector<string> grid(n);
for(int i = 0; i<n; ++i) cin >> grid[i];
pair<int, int> s = {0, 0}, e = {n-1, m-1};
int dis[n][m], trace[n][m]; memset(trace, 0, sizeof trace);
for(int i = 0; i<n; ++i) for(int j = 0; j<m; ++j) dis[i][j] = INF;
dis[s.first][s.second] = 0;
deque<pair<int,int>> q; q.push_back(s);
while(q.size()){
pair<int, int> u = q.front(); q.pop_front();
int current_cell = convert(grid[u.first][u.second]);
if (current_cell == 4) continue;
for(int _dir = 0; _dir < 4; ++_dir){
int dir = (_dir + current_cell) % 4;
pair<int, int> v = {u.first + dx[dir], u.second + dy[dir]};
if (0 <= v.first && v.first < n && 0 <= v.second && v.second < m){
int cur_cost = dis[u.first][u.second] + _dir;
if (minimize(dis[v.first][v.second], cur_cost)){
if (current_cell == 5) q.push_front(v);
else q.push_back(v);
trace[v.first][v.second] = dir;
}
}
}
}
if (dis[e.first][e.second] == INF) cout << -1 << "\n";
else cout << dis[e.first][e.second] << "\n";
}
int main(void){
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
clock_t start = clock();
solve();
cerr << "Time elapsed: " << clock() - start << "ms!\n";
return 0;
}
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