#include <iostream>

 #include <cstdio>

 #include <cstring>

 #include <queue>

 using namespace std;

 #define MAXN 85

 typedef struct node_st {

     int x, y;

     int d, s;

     node_st() {}

     node_st(int xx, int yy, int dd, int ss) {

         x = xx; y = yy; d = dd; s = ss;

     }

 } node_st;

 char map[MAXN][MAXN];

 bool visit[][MAXN][MAXN];

 int direct[][] = {-,,,,,-,,};

 int n, m;

 int bfs(int sx, int sy) {

     int i, j, nx, ny;

     queue<node_st> que;

     node_st node;

     bool flag;

     if (sx== || sx==n- || sy== || sy==m-)

         return ;

     memset(visit, false, sizeof(visit));

     visit[][sx][sy] = visit[][sx][sy] = visit[][sx][sy] = visit[][sx][sy] = true;

     for (i=; i<; ++i) {

         nx = sx + direct[i][];

         ny = sy + direct[i][];

         if (nx< || nx>=n || ny< || ny>=m)

             continue;

         if (map[nx][ny] != '#') {

             que.push(node_st(nx, ny, i, ));

             visit[i][nx][ny] = true;

         }

     }

     while ( !que.empty() ) {

         node = que.front();

         que.pop();

         flag = true;

         // node.d = 0/1 -> south/north

         // node.d = 2/3 -> east/west

         j = (node.d&) ? :;

         for (i=j; i<j+; ++i) {

             nx = node.x + direct[i][];

             ny = node.y + direct[i][];

             if (nx< || nx>=n || ny< || ny>=m)

                 continue;

             if (map[nx][ny] != '#') {

                 flag = false;

                 if (!visit[i][nx][ny]) {

                     if (nx== || nx==n- || ny== || ny==m-)

                         return node.s+;

                     que.push(node_st(nx, ny, i, node.s+));

                     visit[i][nx][ny] = true;

                 }

             }

         }

         if (flag) {

             i = node.d;

             nx = node.x + direct[i][];

             ny = node.y + direct[i][];

             if (nx< || nx>=n || ny< || ny>=m)

                 continue;

             if (map[nx][ny]=='#' || visit[i][nx][ny])

                 continue;

             if(nx== || nx==n- || ny== || ny==m-)

                 return node.s+;

             que.push(node_st(nx, ny, i, node.s+));

             visit[i][nx][ny] = true;

         }

     }

     return -;

 }

 int main() {

     int t, x, y;

     int i, j;

     scanf("%d", &t);

     while (t--) {

         scanf("%d %d", &n, &m);

         for (i=; i<n; ++i) {

             scanf("%s", map[i]);

             for (j=; j<m; ++j)

                 if (map[i][j] == '@') {

                     x = i;

                     y = j;

                 }

         }

         printf("%d\n", bfs(x, y));

     }

     return ;

 }