import sys
input=lambda: sys.stdin.readline().rstrip()
n=int(input())
A=[int(i) for i in input().split()]
Ans=[]
for i in range(n)[::-1]:
  for j in range(i):
    if A[j]>A[j+1]:
      A[j],A[j+1]=A[j+1],A[j]
      Ans.append((j,j+1))
print(len(Ans),flush=True)
for u,v in Ans:
  print(u,v,flush=True)
D=input()