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