You are given a whiteboard with integers from $$$l$$$ to $$$r$$$ written on it, inclusive. Initially, the whiteboard contains the set of integers $$$\{l, l+1, \dots, r\}$$$. You will repeatedly perform the following two operations until the whiteboard is empty:
Your task is to calculate the final total score after the whiteboard becomes empty.
The first line contains an integer $$$T$$$ ($$$1 \le t \le 10^5$$$), the number of testcases. Each of the following $$$t$$$ lines contains two integers $$$l$$$ and $$$r$$$ ($$$1 \le l \le r \le 2 \times 10^9$$$).
For each testcase, print a single integer representing the final total score.
21 33 5
5 7