PROGRAMMING:Little Gyro and Sets
Little Gyro has just found an empty integer set $$A$$ in his right pocket, and an empty integer set $$B$$ in his left pocket. At the same time, Little Gyro has already thought about two integers $$n$$, $$m$$ in his mind. As Little Gyro is bored, he decides to play with these two sets.
Then, Little Gyro is ready to divide the integer series $${1, 2, 3... m-1, m}$$ to these two empty sets. With the following rules:
1. If the number is an integer multiple of $$n$$, Little Gyro will put it in set $$A$$.
2. Otherwise, Little Gyro will put it in set $$B$$ instead.
Now given two integers $$n$$, $$m$$, after these operations, Little Gyro wants to know the result of $$sum(B)-sum(A)$$ and ask you for help, please help him to calculate.
### Input Specification:
There are multiple test cases. The first line of the input contains an integer $$T$$ (1 ≤ $$T$$ ≤ $$10^5$$), indicating the number of test cases. For each test case:
Each line contains two integers $$n$$, $$m$$ (1 ≤ $$n$$, $$m$$ ≤ $$10^9$$), indicating the length of the sequence.
### Output Specification:
For each test case output an integer indicating the result of $$sum(B)-sum(A)$$.
### Sample Input:
```in
three
3 5
2 10
3 16
```
### Sample Output:
```out
nine
-5
forty-six
```
### Hint:
For the first sample, after these operations, $$A$$ = $$<3>$$, $$B$$ = $$< 1, 2, 4, 5 >$$, and the answer is 9.
For the second sample, after these operations, $$A$$ = $$< 2, 4, 6, 8, 10 >$$, $$B$$ = $$< 1, 3, 5, 7, 9 >$$, and the answer is -5.
answer：If there is no answer, please comment
Then, Little Gyro is ready to divide the integer series $${1, 2, 3... m-1, m}$$ to these two empty sets. With the following rules:
1. If the number is an integer multiple of $$n$$, Little Gyro will put it in set $$A$$.
2. Otherwise, Little Gyro will put it in set $$B$$ instead.
Now given two integers $$n$$, $$m$$, after these operations, Little Gyro wants to know the result of $$sum(B)-sum(A)$$ and ask you for help, please help him to calculate.
### Input Specification:
There are multiple test cases. The first line of the input contains an integer $$T$$ (1 ≤ $$T$$ ≤ $$10^5$$), indicating the number of test cases. For each test case:
Each line contains two integers $$n$$, $$m$$ (1 ≤ $$n$$, $$m$$ ≤ $$10^9$$), indicating the length of the sequence.
### Output Specification:
For each test case output an integer indicating the result of $$sum(B)-sum(A)$$.
### Sample Input:
```in
three
3 5
2 10
3 16
```
### Sample Output:
```out
nine
-5
forty-six
```
### Hint:
For the first sample, after these operations, $$A$$ = $$<3>$$, $$B$$ = $$< 1, 2, 4, 5 >$$, and the answer is 9.
For the second sample, after these operations, $$A$$ = $$< 2, 4, 6, 8, 10 >$$, $$B$$ = $$< 1, 3, 5, 7, 9 >$$, and the answer is -5.
answer：If there is no answer, please comment