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;
const int MAXN = 1e7 + 3;
const int INF = 1e9;
const int MOD = 1e9 + 7;
pair<long long, long long> ans[MAXN];
int main() {
  long long x;
  long long a = 1;
  long long i = 1;
  cin >> x;
  int top = 0;
  while (x - a >= 0) {
    long long b = (i + 1) * i / 2;
    if ((x - a) % b == 0) {
      ans[top++] = pair<long long, long long>(i, i + ((x - a) / b));
      if (i != i + ((x - a) / b))
        ans[top++] = pair<long long, long long>(i + ((x - a) / b), i);
    }
    a = (i + 1) * (2 * i + 3) * (i + 2) / 6;
    i++;
  }
  sort(ans, ans + top);
  cout << top << '\n';
  for (int i = 0; i < top; i++) {
    cout << ans[i].first << ' ' << ans[i].second << '\n';
  }
  return 0;
}