package main

import (
	"fmt"
	"sort"
)

func main() {
	var n, a int
	_, _ = fmt.Scan(&n)

	nums := make([]int, n)
	for i := range nums {
		_, _ = fmt.Scan(&a)
		nums[i] = a
	}

	change := make([]string, 0)
	sort.Slice(nums, func(i, j int) bool {
		if nums[i] < nums[j] {
			change = append(change, fmt.Sprintf("%d %d", i, j))
			return true
		}
		return false
	})

	fmt.Println(len(change))
	for _, c := range change {
		fmt.Println(c)
	}
	_, _ = fmt.Scan(&n)
}