Problem Statement

A Kadomatsu sequence is a sequence $A_1, A_2, A_3$ of $3$ elements that satisfies the following 2 conditions.

• $A_1, A_2, A_3$ are all distinct
• Among the $3$ elements, $A_2$ is the largest or $A_2$ is the smallest

The Kadomatsu sequence contest held the other day was poorly received, so we are going to smash Kadomatsu sequences.

You are given a sequence $A$ of length $N$.
You may repeatedly perform the following operation

• Swap the $u$-th element and the $v$-th element of $A$ ($0 \leq u,v < N$ , $u \neq v$)

We thought it might be fun if the number of queries were visible, so this is a reactive problem. Read the Input and Output sections carefully.

Input

$N$
$A_0$ $A_1$ ... $A_{N-1}$
$Dummy$

The 1st line contains the length $N$ of the sequence, and the 2nd line contains the elements of $A$ separated by spaces.
The input on the 3rd line is a dummy input for the reactive judge. Read it after printing your answer. (Your solution might pass without reading it, but read it just in case.)
All inputs are integers and satisfy the following constraints.
$3 \leq N \leq 100$
$1 \leq A_i \leq 100$
$Dummy = -1$

Output

$M$
$u_0$ $v_0$
$u_1$ $v_1$
$\vdots$
$u_{M-1}$ $v_{M-1}$

Print the number of operations on the 1st line, and from the 2nd line onward, print $u$,$v$ ($0 \leq u,v < N$ , $u \neq v$) of the i-th operation, one operation per line.
Finally, flush standard output.
There is no particular limit on the number of swaps, but if there are too many, the judge may get TLE.

Sample

3
1 3 2
-1

2
0 1
1 2

6
1 3 2 2 3 1
-1

1
1 5

10
1 2 3 4 5 6 7 8 9 10
-1

0