因为形成了环,遍历每个点为起始点,并排除相邻点,假设起始点必选。借用House Robber的解法即可。
class Solution { public: int robOne(vector& nums) { if (nums.size() { return 0; } vector v(nums.size() + 1); v[0] = 0; v[1] = nums[0]; for (int i = 1;i < nums.size();i++) { int j = i + 1; if (nums[i] + v[j - 2] > v[j - 1]) { v[j] = nums[i] + v[j-2]; } else { v[j] = v[j-1]; } } return v[nums.size()]; } int rob(vector& nums) { vector numsc; int size = nums.size(); int sum = 0; for (int i = 0;i < size; i++) { numsc.clear(); int tmp = nums[i]; for (int j = i; j < size; j++) { if (j == ((i-1) < 0 ? i - 1 + size : i - 1) || j == ((i+1) >= size ? i + 1 - size : i + 1) || j == i) { numsc.push_back(0); continue; } numsc.push_back(nums[j]); } for (int j = 0; j < i; j++) { if (j == ((i-1) < 0 ? i - 1 + size : i - 1) || j == ((i+1) >= size ? i + 1 - size : i + 1) || j == i) { numsc.push_back(0); continue; } numsc.push_back(nums[j]); } tmp += robOne(numsc); if (tmp >= sum) { sum = tmp; } } return sum; } };