P9673 [ICPC 2022 Jinan R] Quick Sort

When Prof. Pang was young, he wrote the following code for quick sort. Please calculate how many swaps are performed when calling $\text{quicksort}(A, 1, n)$. $A$ is a given permutation with length $n$. 

The first line contains one integer $T~(1\le T \le 10^5)$, the number of test cases. For each test case, the first line contains one positive integer $n~(1\le n \le 5\times 10^5)$. The next line contains $n$ integers $a_1,\ldots, a_n~(1 \le a_i\le n)$ denoting the permutation $A$. It is guaranteed that $a_1,\ldots, a_n$ form a permutation, i.e.~$a_i\neq a_j$ for $i \neq j$. It is guaranteed that the sum of $n$ over all test cases is no more than $5\times 10^5$.

For each test case, output one line containing the number of swaps performed when calling $\text{quicksort}(A, 1, n)$.