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 CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
unsigned long long x;
int main(void) {
  cin >> x;
  vector<pair<unsigned long long, unsigned long long>> p;
  p.push_back(make_pair(1, x));
  if (x != 1) p.push_back(make_pair(x, 1));
  for (unsigned long long i = 2; true; i++) {
    unsigned long long r = 6ULL * x + i * i * i - i;
    unsigned long long m = 3ULL * (i * i + i);
    unsigned long long s = r / m;
    if (s < i) break;
    if (s * m == r) {
      p.push_back(make_pair(i, s));
      if (s != i) p.push_back(make_pair(s, i));
    }
  }
  sort(p.begin(), p.end());
  cout << p.size() << endl;
  for (int i = 0; i < p.size(); i++)
    cout << p[i].first << " " << p[i].second << endl;
  return 0;
}