47 lines
858 B
Markdown
47 lines
858 B
Markdown
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---
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layout: page
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title: House Robber
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last_solved: 2020-06-16
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category: dp
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leetcode_url: https://leetcode.com/problems/house-robber
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status: Solved
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---
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First few cases are trivial.
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Starting from n>=3, it's the max of alternating sequences.
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Gotcha:
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- be careful when to use nums array and when to use dp array
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- make sure to use a different dp array and don't overwrite the given `nums` array
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{% highlight python %}
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nums = [1,2,3,1]
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def rob(nums):
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if not nums: return 0
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if len(nums)==1: return nums[0]
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dp = [1] * len(nums)
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dp[0] = nums[0]
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dp[1] = max(nums[0], nums[1])
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for i in range(2, len(nums)):
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# dp.append( max( nums[i] + dp[i-2], dp[i-1] ) )
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dp[i] = max( nums[i] + dp[i-2], dp[i-1] )
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return dp[-1]
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print(rob(nums))
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{% endhighlight %}
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The dp array looks like ```[1, 2, 4, 4]```
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![image1]()
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