#coding=utf-8
# 1
# 对状态的定义 ： 考虑偷取[x...n-1]范围里的房子


class Solution1(object):
 def rob(self, nums):
 """
 :type nums: List[int]
 :rtype: int
 """

 if not nums:
 return 0


 length = len(nums)

 if length == 1:
 return nums[0]

 memo = [-1 for i in range(length)]
 memo[length-1] = nums[length-1]

 for i in range(length-2 ,-1 ,-1):
 for j in range(i,length):
 if j+2 < length:
 memo[i] = max(memo[i],nums[j] + memo[j+2])
 else:
 memo[i] = max(memo[i],nums[j])

 return memo[i]


# 2
# 对状态的定义： 考虑偷取[0...x]范围里的房子

class Solution2(object):
 def rob(self, nums):
 """
 :type nums: List[int]
 :rtype: int
 """

 if not nums:
 return 0


 length = len(nums)

 if length == 1:
 return nums[0]

 memo = [-1 for i in range(length)]
 memo[0] = nums[0]

 for i in range(1,length):
 for j in range(i,-1,-1):

 if j-2 >=0:
 memo[i] = max(memo[i],nums[j] + memo[j-2])
 else:
 memo[i] = max(memo[i],nums[j])


 return memo[length-1]


s = Solution2()
nm = [1,2,3,1]
print s.rob(nm)