Can I add the problems from the last Balkan OI to a vjudge contest?

Thanks in advance!

I already know how to compute the LIS of an array using a Segment Tree. I've read different materials from different sources

on how to do this, but I've never encountered how to find LIS when the array is muatble.

The input consists of natural number N and M (N <= 2*10^5 and M < N).

Then you are given a permutation of numbers [1, N]
You should sort the given array, but only the following operation is allowed:
Chose a number with index from [0, M-1] and  choose a number from [M, N-1], then swap then.
What is the minimum number of operations to sort the array?

Example: Input:

5 3
1 2 3 5 4

**Steps:**
1. 1 2 5 | 3 4 (swap 3 and 5)
2. 1 2 4 | 3 5 (swap 4 and 5)
3. [1 2 3 | 4 5] (swap 3 and 4, now the array is sorted, total steps = 3)

Any idea on how to solve this problem?

Hi everyone, I started with participation in contests few months ago. My goal(for now) is to become a specialist. What are the must-know techinques to achieve that? Thanks in advance!!!