# House Robber

You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed away. The only constraint stopping you from robbing each of them is that adjacent houses have a security system connected, and it will automatically contact the police if two adjacent houses are broken into on the same night.

Given a list of non-negative integers representing the amount of money in each house, determine the maximum amount of money you can rob tonight without alerting the police.

## Input

The first number contains the number of houses $n(1≤n≤10_{6})$. The second line contains $n$ non-negative integers $a_{1},a_{2},...,a_{n}$, where $a_{i}$ is the amount of money that can be taken from the $i$-th house.

## Output

Print the maximum sum you can steal tonight without triggering a police alert.