N = int(input())
a = [int(t) for t in input().split(' ')]

query = []
m = 0
cnt = -1
while cnt != 0:
    cnt = 0
    for i in range(N-1):
        if a[i] > a[i+1]:
            a[i], a[i+1] = a[i+1], a[i]
            query.append((i, i+1))
            cnt += 1
            m += 1
print(m)
for q in query:
    print(q[0], q[1])
d = input()