5 10
15 10
5 30
15 30
........................................
........................................
........................................
........................................
.........*===================*..........
.........|###################|..........
.........|...................|..........
.........|...................|..........
.........|...................|..........
.........|...................|..........
.........|...................|..........
.........|...................|..........
.........|...................|..........
.........|...................|..........
.........*===================*..........
........................................
........................................
........................................
........................................
........................................