003 给一个mxn的地图。然后车子只能往右走。然后地图里有不能走的block， 还有可以从a点直接传送到b点的传送器。问车子是否可以从左上角走到右下角

this is like those classic problems like warrior can rescue princess or not. or those classic dp problems about how many ways from top left to bottom right.