n = int(input())
A = list(map(int, input().split()))
ans = []
for i in range(n):
    for j in range(n - 1, i, -1):
        if A[j] < A[j - 1]:
            A[j - 1], A[j] = A[j], A[j - 1]
            ans.append((j - 1, j))

print(len(ans))
for row in ans:
    print(*row)
print(end="", flush = True)

input()