Score : $500$ points
You are given a sequence $(P_1,P_2,...,P_N)$ which is a permutation of the integers from $1$ through $N$. You would like to sort this sequence in ascending order by repeating the following operation:
Find the minimum number of operations required. It can be proved that it is actually possible to sort the sequence using this operation.
Input is given from Standard Input in the following format:
$N$ $P_1$ $:$ $P_N$
Print the minimum number of operations required.
4 1 3 2 4
2
For example, the sequence can be sorted in ascending order as follows:
6 3 2 5 1 4 6
4
8 6 3 1 2 7 4 8 5
5