import sys 

N = int(input())
A = list(map(int, input().split()))
ans = []
for i in range(N):
    for j in range(N - 1):
        if A[j] > A[j + 1]:
            A[j], A[j + 1] = A[j + 1], A[j]
            ans.append((j, j + 1))
print(len(ans))
for a, b in ans:
    print(a, b)
sys.stdout.flush()
input()