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- Easy sum

# Easy sum

# Easy sum

Little Kevin had never heard the word 'Infinitum'. So he asked his mentor to explain the word to him. His mentor knew that 'Infinitum' is a very large number. To show him how big Infinitum can be, his mentor gave him a challenge: to sum the numbers from *1* up to *N*. The sum started to get really large and was out of `long long int`

range. And so the lesson was clear.

Now his mentor introduced him to the concept of *mod* and asked him to retain only the remainder instead of the big number. And then, he gave him a formula to compute:

**Input Format**

The first line contains *T*, the number of test cases.

*T* lines follow, each containing 2 space separated integers *N m*

**Output Format**

Print the result on new line corresponding to each test case.

**Constraint**

1 ≤ *T* ≤ 1000

1 ≤ *N* ≤ 10^{9}

1 ≤ *m* ≤ 10^{9}

**Sample Input**

```
3
10 5
10 3
5 5
```

**Sample Output**

```
20
10
10
```

**Explanation**

Case 1: *N* = 10 *m* = 5,

1%5 + 2%5 + 3%5 + 4%5 + 5%5 + 6%5 + 7%5 + 8%5 + 9%5 + 10%5 = 20.

Similar explanation follows for Case 2 and 3.