n=int(input())
a=list(map(int,input().split()))
o=[]
for i in range(n):
	for j in range(n-1):
		if a[j]>a[j+1]:
			o+=[(j,j+1)]
			a[j],a[j+1]=a[j+1],a[j]
print(len(o))
for x,y in o:
	print(x,y)