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;
const long long modulo = 123456789;
const long long oo = 1e18;
const int MAX_SIZE = 100007;
const double PI = acos(-1.0);
int main() {
  vector<pair<long long, long long> > ans;
  long long sq;
  cin >> sq;
  long long limit = 7000007;
  for (long long n = 1; n <= limit; n++) {
    if ((6 * sq) % (n * (n + 1)) == 0) {
      long long br = (6 * sq) / (n * (n + 1)) + n - 1;
      if (br % 3 == 0 && (br / 3) >= n) {
        long long m = br / 3;
        ans.push_back(make_pair(n, m));
        if (m > n) ans.push_back(make_pair(m, n));
      }
    }
  }
  sort(ans.begin(), ans.end());
  cout << ans.size() << endl;
  for (int i = 0; i < ans.size(); i++)
    printf("%I64d %I64d\n", ans[i].first, ans[i].second);
  return 0;
}