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.

<image>

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
uint64_t x;
uint64_t mn = std::numeric_limits<uint64_t>::max();
set<pair<uint64_t, uint64_t> > ans;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.precision(11);
  cout.setf(ios::fixed);
  cin >> x;
  for (uint64_t i = 1; i < mn && i < 2e6; ++i) {
    if ((i * i * i - i + 6LL * x) % (3 * i * (i + 1)) == 0) {
      uint64_t m =
          (uint64_t)((i * i * i - i + 6LL * x) / (3LL * i * (i + 1LL)));
      if (i <= m) {
        ans.insert(make_pair(i, m));
        ans.insert(make_pair(m, i));
      }
      mn = min(m, mn);
    }
  }
  cout << ans.size() << endl;
  for (pair<uint64_t, uint64_t> i : ans) {
    cout << i.first << ' ' << i.second << endl;
  }
  return 0;
}