Problem Statement

You are given a permutation $ P = (P_{1}, P_{2}, P_{3}, \cdots, P_{N})$ consisting of $N$ distinct elements from $1$ to $N$.
You can perform the following operation on the permutation $P$.

• Choose integers $i$ , $j$ ($1 \leq i < j \leq N$) and swap $P_{i}$ and $P_{j}$.

Input

$N$
$P_{1}$ $P_{2}$ $P_{3}$ $\cdots$ $P_{N}$

• $1 \leq N \leq 100$
• $1 \leq P_{i} \leq N$
• For $1 \leq i, j \leq N$, if $i \neq j$ holds, then $P_{i} \neq P_{j}$ holds.
• All inputs are integers.

Output

Output in one line the minimum number of operations required to sort the given permutation $P$ in ascending order. Print a newline at the end.

Sample

3
3 1 2

2

6
3 1 6 5 4 2

4

1
1

0