1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
#include <iostream>
    #include <stdio.h>
    using namespace std;
   
  int invert(int power, int n) {
    return power == -1 ? power : n + 1 - power;
  }

  int main() {
    int k;
    cin >> k;

    int graph[101][2];
    int power[101];

    graph[1][0] = -1;
    graph[1][1] = -1;
    graph[2][0] = 1;
    graph[2][1] = -1;
    power[1] = 1;
    power[2] = 1;
    int max = 2;
    int n = 2;

    while (max < k) {
      n++;
      graph[n][0] = n - 1;
      graph[n][1] = n - 2;
      power[n] = power[n - 1] + power[n - 2];
      max += power[n];
    }

    int range = n - 1;
    int currentPower = power[n];
    while (currentPower < k) {
      n++;
      graph[n][0] = n - 1;
      while (currentPower + power[range] > k) {
        range--;
      }
      currentPower += power[range];
      graph[n][1] = range;
    }

    printf("%d\n", n);
    for (int i = n; i >= 1; i--) {
      printf("%d %d\n", invert(graph[i][0], n), invert(graph[i][1], n));
    }

    return 0;
  }