from sys import stdout
N = int(raw_input())
A = map(int,raw_input().split())
M = 0
op = []
for i in xrange(N):
	for j in xrange(N-i-1):
		if A[j]>A[j+1]:
			A[j],A[j+1]=A[j+1],A[j]
			M+=1
			op.append([j,j+1])
print M
for u,v in op:
	print u,v
stdout.flush()
input()