input()
a=list(map(int,input().split()))
l=[]
for i in range(len(a)):
 for j in range(len(a)-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)//2)
for i in range(0,len(l),2):print(l[i],l[i+1])
input()