#include <bits/stdc++.h>
using namespace std;const int N = 8e2 + 5;
char maze[N][N];
int n, m;
bool vis[N][N][2];
int dx[4] = {-1, 1, 0, 0};
int dy[4] = {0, 0, -1, 1};
struct Point    {int x, y;Point()   {}Point(int x, int y)   : x (x), y (y) {}
};
queue<Point> que[2];
Point mm, gg, gho[2];int get_dis(int x, int y, int ex, int ey)  {return abs (ex - x) + abs (ey - y);
}bool check2(int x, int y, int tim) {for (int i=0; i<2; ++i)  {if (get_dis (x, y, gho[i].x, gho[i].y) <= 2 * tim) return false;}return true;
}bool check(int x, int y, int typ)  {if (x < 1 || x > n || y < 1 || y > m || maze[x][y] == 'X') return false;else   return true;
}void init(void)    {while (!que[0].empty ())   que[0].pop ();while (!que[1].empty ())  que[1].pop ();memset (vis, false, sizeof (vis));
}bool BFS(int typ, int tim) {int sz = que[typ].size ();while (sz--)    {Point u = que[typ].front ();  que[typ].pop ();if (!check (u.x, u.y, typ) || !check2 (u.x, u.y, tim))  continue;for (int i=0; i<4; ++i)  {int tx = u.x + dx[i], ty = u.y + dy[i];if (!check (tx, ty, typ) || !check2 (tx, ty, tim))  continue;if (vis[tx][ty][typ^1])    return true;if (vis[tx][ty][typ])   continue;vis[tx][ty][typ] = true;que[typ].push (Point (tx, ty));}}return false;
}int run(void)  {init ();   vis[mm.x][mm.y][0] = true;vis[gg.x][gg.y][1] = true;que[0].push (Point (mm.x, mm.y));que[1].push (Point (gg.x, gg.y));int step = 0;while (!que[0].empty () || !que[1].empty ())  {++step;for (int i=0; i<3; ++i) {if (BFS (0, step)) return step;}if (BFS (1, step)) return step;}return -1;
}int main(void) {int T; scanf ("%d", &T);while (T--)  {scanf ("%d%d", &n, &m);for (int i=1; i<=n; ++i)   {scanf ("%s", maze[i] + 1);}int t = 0;for (int i=1; i<=n; ++i)   {for (int j=1; j<=m; ++j)    {if (maze[i][j] == 'M') {mm.x = i; mm.y = j;}else if (maze[i][j] == 'G')  {gg.x = i; gg.y = j;}else if (maze[i][j] == 'Z')  {gho[t].x = i; gho[t++].y = j;}}}printf ("%d\n", run ());}return 0;
}