#include <iostream>
#include <vector>
#include <queue>
#include <map>
#include <tuple>
using namespace std;
const int INF = 1e9;
int dx[4] = {0, 1, 0, -1}; // E, S, W, N
int dy[4] = {1, 0, -1, 0};
int main() {
int n, m;
cin >> n >> m;
vector<vector<char>> grid(n, vector<char>(m));
map<char, int> dirMap = {{'E', 0}, {'S', 1}, {'W', 2}, {'N', 3}};
for (int i = 0; i < n; ++i)
for (int j = 0; j < m; ++j)
cin >> grid[i][j];
vector<vector<int>> dist(n, vector<int>(m, INF));
priority_queue<tuple<int, int, int>, vector<tuple<int, int, int>>, greater<>> pq;
dist[0][0] = 0;
pq.emplace(0, 0, 0); // (rotations, x, y)
while (!pq.empty()) {
auto [rot, x, y] = pq.top(); pq.pop();
if (make_pair(x, y) == make_pair(n - 1, m - 1)) {
cout << rot << endl;
return 0;
}
if (grid[x][y] == 'X') continue; // dead cell
int currentDir = dirMap[grid[x][y]];
for (int newDir = 0; newDir < 4; ++newDir) {
int nx = x + dx[newDir];
int ny = y + dy[newDir];
if (nx < 0 || ny < 0 || nx >= n || ny >= m) continue;
if (grid[nx][ny] == 'X' && !(nx == n - 1 && ny == m - 1)) continue;
int rotCost = (newDir - currentDir + 4) % 4;
if (dist[nx][ny] > dist[x][y] + rotCost) {
dist[nx][ny] = dist[x][y] + rotCost;
pq.emplace(dist[nx][ny], nx, ny);
}
}
}
cout << -1 << endl;
return 0;
}
