Problem: Spongebob is already tired trying to reason his weird actions and calculations, so he simply asked you to find all pairs of n and m, such that there are exactly x distinct squares in the table consisting of n rows and m columns. For example, in a 3 × 5 table there are 15 squares with side one, 8 squares with side two and 3 squares with side three. The total number of distinct squares in a 3 × 5 table is 15 + 8 + 3 = 26.

Input

The first line of the input contains a single integer x (1 ≤ x ≤ 1018) — the number of squares inside the tables Spongebob is interested in.

Output

First print a single integer k — the number of tables with exactly x distinct squares inside.

Then print k pairs of integers describing the tables. Print the pairs in the order of increasing n, and in case of equality — in the order of increasing m.

Examples

Input

26


Output

6
1 26
2 9
3 5
5 3
9 2
26 1


Input

2


Output

2
1 2
2 1


Input

8


Output

4
1 8
2 3
3 2
8 1

Note

In a 1 × 2 table there are 2 1 × 1 squares. So, 2 distinct squares in total.

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In a 2 × 3 table there are 6 1 × 1 squares and 2 2 × 2 squares. That is equal to 8 squares in total.

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Solution (in PYTHON):

Solution:
x = int(raw_input())

def f(m, n):
	return 6*m*n*n - 3*(m+n)*(n-1)*n + (n-1)*n*(2*n-1)

all = []
for n in xrange(1,int(1.5*10**6 + 1)):
	if (6*x) % n > 0:
		continue
	l = n
	r = x
	res = l
	while l <= r:
		mid = (l + r) / 2
		if f(mid, n) <= 6*x:
			res = mid
			l = mid + 1
		else:
			r = mid - 1
	if f(res, n) == 6*x:
		all.append((res, n))
		if res != n:
			all.append((n, res))

all = sorted(all, key = lambda x: (x[0], x[1]))
print len(all)
for p in all:
	print p[0], p[1]