Get-Shortest-Path-by-BFS

Get Shortest Path by BFS click on the S or E point to delete them click on the road to place an S point on it if there is no S point yet or both S and E do not exist on the road click on the road to place an E point on it if there is no E point on the road yet click on a non-road area to place a road tile on the map click on a road tile to change it to a non-road tile. Each time when the road or the S and E points changed, the roadmap data will be saved