LeetCode 213. House Robber II

Note: This is an extension of House Robber.
After robbing those houses on that street, the thief has found himself a new place for his thievery so that he will not get too much attention. This time, all houses at this place are arranged in a circle. That means the first house is the neighbor of the last one. Meanwhile, the security system for these houses remain the same as for those in the previous street.
Given a list of non-negative integers representing the amount of money of each house, determine the maximum amount of money you can rob tonight without alerting the police.

分析:这题是上一题House Robber的升级版~~新加了环形的街道biu biu biu~~
所以就会考虑到,最后一个和第一个房子是不能够同时进入的~要不然会告诉警察叔叔~~
所以分为两种情况~~
0.不包括最后一个屋子~就抢劫0~n-2号屋子~
1.不包括第一个屋子~就抢劫1~n-1号屋子~
这样的话,return上面两种情况的最大值就好了~调用两次子函数求值,主函数取其最大值返回~