萌新求助，请大佬解释一下#3数据，QwQ

P1519 [USACO2.4] 穿越栅栏 Overfencing

![](http://images2015.cnblogs.com/blog/1022747/201609/1022747-20160916163626883-1898155526.jpg)
by xyf007 @ 2019-08-08 08:23:30

![](http://images2015.cnblogs.com/blog/1022747/201609/1022747-20160916163626883-1898155526.jpg)
by SSStrayer @ 2019-08-08 08:37:17