代码随想录：打家劫舍二

class Solution {
public:
    int rob(vector<int>& nums) {
        //两种情况，考虑偷头，考虑偷尾
        if(nums.size()==1)return nums[0];
        if(nums.size()==2)return max(nums[0],nums[1]);
        int a = rob_common(vector<int>(nums.begin(),nums.end()-1));
        int b = rob_common(vector<int>(nums.begin()+1,nums.end()));
        return max(a,b);
    }

    int rob_common(vector<int> nums) {
        vector<int> dp = vector<int>(nums.size(), 0);

        dp[0] = nums[0];
        dp[1] = max(nums[0], nums[1]);

        for (int i = 2; i < nums.size(); i++) {
            dp[i] = max(dp[i - 1], dp[i - 2] + nums[i]);
        }

        return dp[nums.size() - 1];
    }
};