houseRobberII.py

#! /usr/bin/env python3
# -*- coding: utf-8 -*-

# Source: https://leetcode.com/problems/house-robber-ii/
# Author: Miao Zhang
# Date:   2021-01-26

class Solution:
    def rob(self, nums: List[int]) -> int:
        if not nums:
            return 0
        n = len(nums)
        if n == 1: return nums[0]
        if n == 2: return max(nums[0], nums[1])
        return max(self.robTotal(nums[0: n - 1]), self.robTotal(nums[1: n]))
    
    def robTotal(self, nums: List[int]) -> int:
        if not nums:
            return 0
        n = len(nums)
        if n == 1: return nums[0]
        if n == 2: return max(nums[0], nums[1])
        dp = [0] * len(nums)
        dp[0] = nums[0]
        dp[1] = max(nums[0], nums[1])
        for i in range(2, n):
            dp[i] = max(dp[i - 1], dp[i - 2] + nums[i])
        return dp[n - 1]