static object Solve()
{
var(h, w) = Read2();
var sp = GraphConsole.ReadPoint();
var ep = GraphConsole.ReadPoint();
var s = GraphConsole.ReadEnclosedGrid(ref h, ref w);
int ToId(Point p) => p.i * w + p.j;
int ToId2(int i, int j) => i * w + j;
Point FromId(int id) => new Point(id / w, id % w);
var u_tate = new bool[h, w];
var u_yoko = new bool[h, w];
var r = ShortestPathCore.Bfs(h * w, pid =>
{
var(pi, pj) = FromId(pid);
var nexts = new List <int>();
if (!u_tate[pi, pj])
{
u_tate[pi, pj] = true;
for (int i = pi - 1; i >= 0 && s[i][pj] == '.'; i--)
{
u_tate[i, pj] = true;
nexts.Add(ToId2(i, pj));
}
for (int i = pi + 1; i < h && s[i][pj] == '.'; i++)
{
u_tate[i, pj] = true;
nexts.Add(ToId2(i, pj));
}
}
if (!u_yoko[pi, pj])
{
u_yoko[pi, pj] = true;
for (int j = pj - 1; j >= 0 && s[pi][j] == '.'; j--)
{
u_yoko[pi, j] = true;
nexts.Add(ToId2(pi, j));
}
for (int j = pj + 1; j < w && s[pi][j] == '.'; j++)
{
u_yoko[pi, j] = true;
nexts.Add(ToId2(pi, j));
}
}
return(nexts.ToArray());
},
ToId(sp), ToId(ep));
return(r[ToId(ep)] - 1);
}
public static UnweightedResult Bfs(int vertexesCount, int[][] edges, bool directed, int startVertexId, int endVertexId = -1)
{
var map = UnweightedEdgesToMap(vertexesCount, edges, directed);
return(ShortestPathCore.Bfs(vertexesCount, v => map[v], startVertexId, endVertexId));
}
public UnweightedResult Bfs(int startVertex, int endVertex = -1)
{
return(ShortestPathCore.Bfs(VertexesCount, v => this[v], startVertex, endVertex));
}
public UnweightedResult Bfs(Point startVertex, Point endVertex)
{
return(ShortestPathCore.Bfs(Height, Width, v => this[v], startVertex, endVertex));
}
