input()
a=list(map(int,input().split()))
c=len(a)
l=[]
for i in range(c):
 for j in range(c-i-1):
  if a[j]>a[j+1]:l+=[[j,j+1]];a[j],a[j+1]=a[j+1],a[j]
print(len(l))
for i in l:print(i[0],i[1])
input()