B. Split Sort
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

You are given a permutation$$$^{\dagger}$$$ $$$p_1, p_2, \ldots, p_n$$$ of integers $$$1$$$ to $$$n$$$.

You can change the current permutation by applying the following operation several (possibly, zero) times:

  • choose some $$$x$$$ ($$$2 \le x \le n$$$);
  • create a new permutation by:
    • first, writing down all elements of $$$p$$$ that are less than $$$x$$$, without changing their order;
    • second, writing down all elements of $$$p$$$ that are greater than or equal to $$$x$$$, without changing their order;
  • replace $$$p$$$ with the newly created permutation.

For example, if the permutation used to be $$$[6, 4, 3, 5, 2, 1]$$$ and you choose $$$x = 4$$$, then you will first write down $$$[3, 2, 1]$$$, then append this with $$$[6, 4, 5]$$$. So the initial permutation will be replaced by $$$[3, 2, 1, 6, 4, 5]$$$.

Find the minimum number of operations you need to achieve $$$p_i = i$$$ for $$$i = 1, 2, \ldots, n$$$. We can show that it is always possible to do so.

$$$^{\dagger}$$$ A permutation of length $$$n$$$ is an array consisting of $$$n$$$ distinct integers from $$$1$$$ to $$$n$$$ in arbitrary order. For example, $$$[2,3,1,5,4]$$$ is a permutation, but $$$[1,2,2]$$$ is not a permutation ($$$2$$$ appears twice in the array), and $$$[1,3,4]$$$ is also not a permutation ($$$n=3$$$ but there is $$$4$$$ in the array).

Input

Each test contains multiple test cases. The first line contains the number of test cases $$$t$$$ ($$$1 \le t \le 1000$$$). The description of the test cases follows.

The first line of each test case contains one integer $$$n$$$ ($$$1 \le n \le 100\,000$$$).

The second line of each test case contains $$$n$$$ integers $$$p_1, p_2, \ldots, p_n$$$ ($$$1 \le p_i \le n$$$). It is guaranteed that $$$p_1, p_2, \ldots, p_n$$$ is a permutation.

It is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$100\,000$$$.

Output

For each test case, output the answer on a separate line.

Example
Input
5
1
1
2
2 1
6
6 4 3 5 2 1
3
3 1 2
19
10 19 7 1 17 11 8 5 12 9 4 18 14 2 6 15 3 16 13
Output
0
1
4
1
7
Note

In the first test case, $$$n = 1$$$ and $$$p_1 = 1$$$, so there is nothing left to do.

In the second test case, we can choose $$$x = 2$$$ and we immediately obtain $$$p_1 = 1$$$, $$$p_2 = 2$$$.

In the third test case, we can achieve the minimum number of operations in the following way:

  1. $$$x = 4$$$: $$$[6, 4, 3, 5, 2, 1] \rightarrow [3, 2, 1, 6, 4, 5]$$$;
  2. $$$x = 6$$$: $$$[3, 2, 1, 6, 4, 5] \rightarrow [3, 2, 1, 4, 5, 6]$$$;
  3. $$$x = 3$$$: $$$[3, 2, 1, 4, 5, 6] \rightarrow [2, 1, 3, 4, 5, 6]$$$;
  4. $$$x = 2$$$: $$$[2, 1, 3, 4, 5, 6] \rightarrow [1, 2, 3, 4, 5, 6]$$$.