/*
 *  Description: 生化武器2 (http://noobdream.com/DreamJudge/Issue/page/1124/)
 *  Author: 鱼翔浅底
 *  Date: 2021-02-17 12:30:09
 */
#include <cstdlib>
#include <cstdio>
#include <cstring>
#include <queue>

using namespace std;

#define maxn 101

typedef struct
{
    char map[maxn][maxn];
    int sx, sy;
    int gx, gy;
    int n, m, t;
} ROOM;
typedef struct
{
    int x, y;
    int step;
} NODE;

bool BFS(ROOM &r)
{
    char vis[maxn][maxn][2]; //标志有没有被访问过
    const int dir[4][2] = {
        -1, 0, //上
        1, 0,  //下
        0, -1, //左
        0, 1   //右
    };         //方向
    queue<NODE> Gq, Sq;

    memset(vis, 0, sizeof(vis));
    Gq.push(NODE{r.gx, r.gy, 0});
    vis[r.gx][r.gy][0] = 1;
    Sq.push(NODE{r.sx, r.sy, 0});
    vis[r.sx][r.sy][1] = 1;

    int cnt = 0;
    while (!Gq.empty())
    {
        //毒气扩散
        while (!Gq.empty())
        {
            NODE now = Gq.front();
           ...