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赛氪OJ-专注于算法竞赛的在线评测系统 (saikr.com)

#include <iostream>
#include <vector>
#include <cstring>
using namespace std;

typedef pair<int, int> PII;
const int N = 510;
char g[N][N];
int n, m;
bool vis[N][N];
int flag;

int dx[] = {-1, 0, 1, 0};
int dy[] = {0, 1, 0, -1};
bool dfs(int x, int y) {

	if (x < 0 || x >= n || y < 0 || y >= m || g[x][y] == '#' || vis[x][y])
		return false;

	if (g[x][y] == 'E') {
		return true;
	}



	vis[x][y] = true;

	for (int i = 0; i < 4; i++) {

		int tx = x + dx[i], ty = y + dy[i];


		if (dfs(tx, ty))
			return true;
	}
	return false;
}

int main() {
	cin >> n >> m;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < m; j++) {
			cin >> g[i][j];
		}
	}
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < m; j++) {
			if (g[i][j] == 'S') {
				memset(vis, false, sizeof vis);
				if (dfs(i, j)) {
					cout << "Yes" << endl;
					return 0;
				}
			}
		}
	}

	cout << "No" << endl;
	return 0;
}