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(i+1,N):
		if A[j]<A[j-1]:
			A[j-1],A[j]=A[j],A[j-1]
			M+=1
			op.append([j-1,j])
print M
for u,v in op:
	print u,v
stdout.flush()
input()