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())

sq = 0
li = 0

i = 1
res = []

while x-sq > li:
    sq += i*i
    li += i

    if (x-sq) % li == 0:
        res.append ((i, i+(x-sq)/li))

    i += 1

res_len = 2*len(res)
if res[-1][0] == res[-1][1]:
    res_len -= 1

print res_len
    
for item in res:
    print item[0],item[1]

if res[-1][0] == res[-1][1]:
    res = res[:-1]

res.reverse()
for item in res:
    print item[1],item[0]