489A - SwapSort - CodeForces Solution

n = int(input())
v = [int(x) for x in input().split()]
final = v.copy()

final = sorted(final)
ans = []
for i in range(n):
	if v[i] == final[i]:
		continue
	else:
		j = i + 1
		while j < n and v[j] != final[i]:
			j += 1
		v[i], v[j] = v[j], v[i]
		ans.append((i, j))
print(len(ans))
for i, j in ans:
	print(i, j)