#GYM104683E. L-shaped Dominoes
L-shaped Dominoes
Description
You are given a $2*n$ grid, where each cell contains an integer (not necessarily non-negative).
Your task is to find a way to place non-overlapping L-shaped dominoes on this grid, so that the sum of integers on the cells covered by the dominoes is maximum.
An L-shaped domino can be seen as a $2*2$ domino obtained by removing a $1*1$ domino.
For example,for the following $2*5$ grid, the optimal way is shown in the right picture.
![]() | ![]() |
Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^5$). The description of the test cases follows.
The first line of each testcase contains a single integer $n$ ($2 \le n \le 2\cdot 10^5$).
The second line contains $n$ integers $a_1,a_2,\ldots, a_n$ ($-10^9 \le a_i \le 10^9$),representing the $n$ numbers in the first row of this grid.
The third line of contains $n$ integers $b_1,b_2,\ldots, b_n$ ($-10^9 \le b_i \le 10^9$),representing the $n$ numbers in the second row of this grid.
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
For each test case, print a single integer in a new line — the maximum sum you can get.
Input
Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^5$). The description of the test cases follows.
The first line of each testcase contains a single integer $n$ ($2 \le n \le 2\cdot 10^5$).
The second line contains $n$ integers $a_1,a_2,\ldots, a_n$ ($-10^9 \le a_i \le 10^9$),representing the $n$ numbers in the first row of this grid.
The third line of contains $n$ integers $b_1,b_2,\ldots, b_n$ ($-10^9 \le b_i \le 10^9$),representing the $n$ numbers in the second row of this grid.
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
Output
For each test case, print a single integer in a new line — the maximum sum you can get.
3
3
-1 -1 -1
-1 -1 -1
5
10 9 10 10 9
10 10 -20 10 9
6
123 -183 100 -213 901 910
281 -182 281 211 129 -999
0
60
2754
Note
Test Case $1$:
You don't need to place any dominoes.
Test Case $2$:
The optimal way is shown in the picture above.