Greetings
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.
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 $2 \cdot 10^5$.
For each test case, output a single integer denoting the number of greetings that will happen.
Input
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
For each test case, output a single integer denoting the number of greetings that will happen.
5
2
2 3
1 4
6
2 6
3 9
4 5
1 8
7 10
-2 100
4
-10 10
-5 5
-12 12
-13 13
5
-4 9
-2 5
3 4
6 7
8 10
4
1 2
3 4
5 6
7 8
1
9
6
4
0
Note
In the first test case, the two people will meet at point $3$ and greet each other.