You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in python3.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```python
<your code here>
```

Execution time limit: 1.0 seconds
Memory limit: 256.0 MB

# Problem
Ayoub thinks that he is a very smart person, so he created a function $$$f(s)$$$, where $$$s$$$ is a binary string (a string which contains only symbols "0" and "1"). The function $$$f(s)$$$ is equal to the number of substrings in the string $$$s$$$ that contains at least one symbol, that is equal to "1".

More formally, $$$f(s)$$$ is equal to the number of pairs of integers $$$(l, r)$$$, such that $$$1 \leq l \leq r \leq |s|$$$ (where $$$|s|$$$ is equal to the length of string $$$s$$$), such that at least one of the symbols $$$s_l, s_{l+1}, \ldots, s_r$$$ is equal to "1".

For example, if $$$s = $$$"01010" then $$$f(s) = 12$$$, because there are $$$12$$$ such pairs $$$(l, r)$$$: $$$(1, 2), (1, 3), (1, 4), (1, 5), (2, 2), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4), (4, 5)$$$.

Ayoub also thinks that he is smarter than Mahmoud so he gave him two integers $$$n$$$ and $$$m$$$ and asked him this problem. For all binary strings $$$s$$$ of length $$$n$$$ which contains exactly $$$m$$$ symbols equal to "1", find the maximum value of $$$f(s)$$$.

Mahmoud couldn't solve the problem so he asked you for help. Can you help him?

## Input Format
The input consists of multiple test cases. The first line contains a single integer $$$t$$$ ($$$1 \leq t \leq 10^5$$$)  — the number of test cases. The description of the test cases follows.

The only line for each test case contains two integers $$$n$$$, $$$m$$$ ($$$1 \leq n \leq 10^{9}$$$, $$$0 \leq m \leq n$$$) — the length of the string and the number of symbols equal to "1" in it.

## Output Format
For every test case print one integer number — the maximum value of $$$f(s)$$$ over all strings $$$s$$$ of length $$$n$$$, which has exactly $$$m$$$ symbols, equal to "1".

## Examples
```input
5
3 1
3 2
3 3
4 0
5 2
```
```output
4
5
6
0
12
```

## Note
In the first test case, there exists only $$$3$$$ strings of length $$$3$$$, which has exactly $$$1$$$ symbol, equal to "1". These strings are: $$$s_1 = $$$"100", $$$s_2 = $$$"010", $$$s_3 = $$$"001". The values of $$$f$$$ for them are: $$$f(s_1) = 3, f(s_2) = 4, f(s_3) = 3$$$, so the maximum value is $$$4$$$ and the answer is $$$4$$$.

In the second test case, the string $$$s$$$ with the maximum value is "101".

In the third test case, the string $$$s$$$ with the maximum value is "111".

In the fourth test case, the only string $$$s$$$ of length $$$4$$$, which has exactly $$$0$$$ symbols, equal to "1" is "0000" and the value of $$$f$$$ for that string is $$$0$$$, so the answer is $$$0$$$.

In the fifth test case, the string $$$s$$$ with the maximum value is "01010" and it is described as an example in the problem statement.

Now solve the problem and return the code.