def gameValue(nums):
    def valueStartingAt(i):
        """Return the game value of nums[i:]"""
        if i == len(nums):
            return 0
        elif i == len(nums)-1:
            return nums[i]
        else:
            return max(nums[i] - valueStartingAt(i+1),
                       nums[i] + nums[i+1] - valueStartingAt(i+2))
    return valueStartingAt(0)