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())
n = 1
ans = []
n_ans = 0
while 1:
	nume = x + n*(n**2-1)/6
	deno = n*(n+1)/2
	if n*deno > nume: break
	if nume % deno == 0:
		ans.append((n,nume/deno))
		n_ans += 1
	n += 1
ub = 1 if ans[n_ans-1][0] == ans[n_ans-1][1] else 0
print n_ans*2 - ub
for i in xrange(n_ans):
	print ans[i][0],ans[i][1]
for i in xrange(n_ans-ub-1,-1,-1):
	print ans[i][1],ans[i][0]