Description: There are $$$n$$$ people on the number line; the $$$i$$$-th person is at point $$$a_i$$$ and wants to go to point $$$b_i$$$. For each person, $$$a_i < b_i$$$, and the starting and ending points of all people are distinct. (That is, all of the $$$2n$$$ numbers $$$a_1, a_2, \dots, a_n, b_1, b_2, \dots, b_n$$$ are distinct.) All the people will start moving simultaneously at a speed of $$$1$$$ unit per second until they reach their final point $$$b_i$$$. When two people meet at the same point, they will greet each other once. How many greetings will there be? Note that a person can still greet other people even if they have reached their final point. Input Format: The first line of the input contains a single integer $$$t$$$ ($$$1 \le t \le 10^4$$$) — the number of test cases. The description of test cases follows. The first line of each test case contains a single integer $$$n$$$ ($$$1 \le n \le 2 \cdot 10^5$$$) — the number of people. Then $$$n$$$ lines follow, the $$$i$$$-th of which contains two integers $$$a_i$$$ and $$$b_i$$$ ($$$-10^9 \leq a_i < b_i \leq 10^9$$$) — the starting and ending positions of each person. For each test case, all of the $$$2n$$$ numbers $$$a_1, a_2, \dots, a_n, b_1, b_2, \dots, b_n$$$ are distinct. The sum of $$$n$$$ over all test cases does not exceed $$$2 \cdot 10^5$$$. Output Format: For each test case, output a single integer denoting the number of greetings that will happen. Note: In the first test case, the two people will meet at point $$$3$$$ and greet each other.