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#include <cstdio>
#include <cmath>
#include <iostream>
#include <algorithm>
#include <queue>
#include <list>
#include <vector>
#include <map>
#include <set>
#include <string>
#include <cstring>
#include <cassert>
#include <limits.h>

using namespace std;

typedef long long LL;
typedef long double LD;

typedef vector<int> VI;
typedef pair<int,int> PII;
#define REP(i,n) for(int i=0;i<(n);i++)
#define FOR(i,a,b) for(VAR(i,a);i<=(b);++i)
#define FORD(i,a,b) for(VAR(i,a);i>=(b);--i)
#define FORE(a,b) for(VAR(a,(b).begin());a!=(b).end();++a)
#define VAR(a,b) __typeof(b) a=(b)
#define SIZE(a) ((int)((a).size()))
#define ALL(x) (x).begin(),(x).end()
#define CLR(x,a) memset(x,a,sizeof(x))
#define ZERO(x) memset(x,0,sizeof(x))
#define S(t,i) scanf("%" ## t, &i)
#define SI(i) scanf("%d", &i)

const int INF=INT_MAX;
const int MAXN=1000+5;

int n;
int f[] = {0, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811, 514229, 832040, 1346269, 2178309, 3524578, 5702887, 9227465, 14930352, 24157817, 39088169, 63245986, 102334155, 165580141, 267914296, 433494437, 701408733, 1134903170, 1836311903};

int main() {
    ios_base::sync_with_stdio(0);
    
    SI(n);
    
    list<pair<int, int>> e;
    
    queue<int> q;
    
    while (n) {
        int i = 0;
        while (f[i+1] <= n) {
            i++;
        }
        n -= f[i];
        q.push(100 - i);
        //printf("%d\n", f[i]);
    }
    
    int ei = 1;
    while (q.size() > 2) {
        int v1 = q.front();
        q.pop();
        int v2 = q.front();
        q.pop();
        q.push(++ei);
        e.push_back(make_pair(v1, v2));
    }
    
    printf("100\n");
    if (q.size() == 1) {
        printf("%d -1\n", q.front());
    } else {
        int v1 = q.front();
        q.pop();
        int v2 = q.front();
        q.pop();
        printf("%d %d\n", v1, v2);
        FORE(eit, e) {
            pair<int, int> p = *eit;
            printf("%d %d\n", p.first, p.second);
        }
    }

    FOR(i, ei + 1, 49) {
        printf("-1 -1\n");
    }
    
    FOR(i, 51, 99) {
        printf("%d %d\n", i, i+1);
    }
    printf("100 -1\n");
    printf("-1 -1\n");
    
    return 0;
}