AT_agc076_e [AGC076E] Squared Norm Maximization
Description
You are given $ N $ pairs of integers $ (A_1,B_1),(A_2,B_2),\cdots,(A_N,B_N) $ .
For a subset $ s $ of $ \{1,2,\cdots,N\} $ , we define its **score** as follows:
- $ (\sum_{i \in s} A_i)^2 + (\sum_{i \in s} B_i)^2 - 3 \sum_{i \in s} (A_i^2+B_i^2) $
Find the maximum possible value of the score.
Solve $ T $ cases for one input.
Input Format
The input is given from Standard Input in the following format:
> $ T $ $ case_1 $ $ case_2 $ $ \vdots $ $ case_T $
Each test case is given in the following format:
> $ N $ $ A_1 $ $ B_1 $ $ A_2 $ $ B_2 $ $ \vdots $ $ A_N $ $ B_N $
Output Format
Output $ T $ lines. The $ i $ -th line should contain the answer for the $ i $ -th case.
Explanation/Hint
### Sample Explanation 1
In the first case, if $ s=\{\} $ , the score is $ 0 $ , which is the maximum.
In the second case, if $ s=\{1,2,3,4\} $ , the score is $ 4 $ , which is the maximum.
### Constraints
- $ 1 \leq T \leq 250000 $
- $ 1 \leq N \leq 250000 $
- $ \sum_{1 \leq i \leq N} |A_i| \leq 10^9 $
- $ \sum_{1 \leq i \leq N} |B_i| \leq 10^9 $
- The sum of $ N $ over the $ T $ cases is at most $ 250000 $ .
- All input values are integers.