Java for LeetCode 213 House Robber II

標籤：

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.

解題思路：

可以分解為兩種情況：包含nums[0]和不包含nums[0]，分別求解算出最大即可，JAVA實現如下；

    public int rob(int[] nums) {if (nums == null || nums.length == 0)return 0;else if (nums.length <= 2)return Math.max(nums[0], nums[nums.length - 1]);else if(nums.length==3)return Math.max(nums[0], Math.max(nums[1],nums[2]));int res = 0;int[] dp = new int[nums.length];dp[0] = nums[0];dp[2] = nums[0] + nums[2];dp[3] = nums[0] + nums[3];for (int i = 4; i < nums.length-1; i++)dp[i] = nums[i] + Math.max(dp[i - 2], dp[i - 3]);res=Math.max(dp[nums.length-2],dp[nums.length-3]);dp[1] = nums[1];dp[2] = nums[2];dp[3] = nums[3] + nums[1];for (int i = 4; i < nums.length; i++)dp[i] = nums[i] + Math.max(dp[i - 2], dp[i - 3]);return Math.max(res, Math.max(dp[nums.length-1],dp[nums.length-2]));    }

 

Java for LeetCode 213 House Robber II