198

Author: tech-cow

README.md

@@ -108,6 +108,9 @@ Success is like pregnancy, Everybody congratulates you but nobody knows how many
 |-----|-------| -------- | ---- | ------|------------|-----|
 |70|[Climbing Stairs](https://leetcode.com/problems/climbing-stairs/#/solutions)| [Python [Yu]](./dp/70.py) | _O(N)_| _O(1)_  | Easy| |
 |53|[Maximum Subarray](https://leetcode.com/problems/maximum-subarray/#/description)| [Python [Yu]](./dp/53.py) | _O(N)_| _O(N)_  | Easy|[公瑾讲解](https://youtu.be/4tfhDdgu76E) |
+|198|[House Robber](https://leetcode.com/problems/house-robber/#/description)| [Python [Yu]](./dp/198.py) | _O(N)_| _O(N)_  | Easy|[公瑾讲解](https://youtu.be/QSjPkgyxCaQ) |
+
+
 
 ## Dynamic Programming Medium
 |  #  | Title | Solution | Time | Space | Difficulty | Note|

dp/198.py

@@ -0,0 +1,43 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# Author: Yu Zhou
+# 198. House Robber
+
+# DP的思路是比对dp[i-2]+nums[i] 和dp[i-1]的值
+# 状态：从0到i，不能选择相邻节点得到的最大值
+
+# DP
+# 时间/空间 O(N)
+
+class Solution(object):
+    def rob(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: int
+        数学公式
+        f(0) = nums[0]
+        f(1) = max(f(0), f(1))
+        f(2) = max(nums(2)+ f(0), f(1))
+        f(3) = max(nums(3)+ f(1), f(2))
+        .
+        .
+        f(n) = max(nums(n) + f(n-2), f(n-1))
+        """
+        # Edge
+        if not nums:
+            return 0
+        if len(nums) == 1:
+            return nums[0]
+
+
+        # Creating dp
+        dp = [0 for i in xrange(len(nums))]
+        dp[0] = nums[0]
+        dp[1] = max(nums[0], nums[1])
+
+        # DP
+        for i in xrange(2, len(nums)):
+            dp[i] = max(nums[i] + dp[i-2], dp[i-1])
+
+        return dp[-1]