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#include<bits/stdc++.h>
using namespace std;
 
 
int arr[21][21];
 
int vis[21][21];
int dist[21][21];
 
int dr[]={1,0,-1,0};
int dc[]={0,1,0,-1};
 
int n, m;
 
int safe(int x,int y)
{
  return x>=0 && y>=0 && x<n && y<m;
}
 
 
void bfs(int sx, int sy, int dx, int dy)
{
	  queue< pair<int,int> > q;
	  q.push(make_pair(sx,sy));
 
      vis[sx][sy]=1;
      dist[sx][sy]=0;
 
	  while(!q.empty())
	  {
			int r=q.front().first;
			int c=q.front().second;
 
            if(r==dx && c==dy) break;
 
            q.pop();
	    	for(int i=0; i<4; i++)
	    	{
		    	int a = r + dr[i];
		    	int b = c + dc[i];
 
                if(safe(a,b)  && !vis[a][b] && arr[a][b])
                {
                  q.push(make_pair(a,b));
                  dist[a][b] = dist[r][c]+1;
                  vis[a][b]=1;
              }
		  }
	  }
}
 
 
int main()
{
    ios::sync_with_stdio(false);
    int tc, dx, dy;
 
    cin>>tc;
    while(tc--)
    {
        cin>>n>>m;
 
        memset(arr,0,sizeof(arr));
        memset(vis, 0, sizeof(vis));
        memset(dist, 0, sizeof(dist));
 
        for(int i=0; i<n; i++)
        {
           for(int j=0; j<m; j++)
           {
              cin>>arr[i][j];
           }
        }
        cin>>dx>>dy;
 
        bfs(0,0,dx,dy);
       if(!vis[dx][dy])
         cout<<"-1\n";
       else
         cout<<dist[dx][dy]<<endl;
    }
    return 0;
}