House Robber

You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed. The only constraint stopping you is that adjacent houses have security systems connected — if two adjacent houses are broken into on the same night, the police will be alerted.

Given an integer array nums representing the amount of money at each house, return the maximum amount of money you can rob tonight without alerting the police.

Examples

Example 1:

Input: nums = [1,2,3,1]

Output: 4

Explanation: Rob house 0 (money = 1) and then rob house 2 (money = 3). Total = 1 + 3 = 4.

Example 2:

Input: nums = [2,7,9,3,1]

Output: 12

Explanation: Rob house 0 (money = 2), house 2 (money = 9), and house 4 (money = 1). Total = 2 + 9 + 1 = 12.

Example 3:

Input: nums = [2,1,1,2]

Output: 4

Explanation: Rob house 0 (money = 2) and house 3 (money = 2). Total = 2 + 2 = 4.

Constraints

• 1 <= nums.length <= 100
• 0 <= nums[i] <= 400