#include <bits/stdc++.h>

using namespace std;
int k;
const int N = 109;
int n = 100, fib[N], max_ind;
pair<int, int> dag[N];

vector<int> find_fibsum(int num)
{
    vector<int> fib_ind;
    for(int i = max_ind; i >= 1; i--) {
        if(num - fib[i] >= 0) {
            fib_ind.push_back(i);
            num -= fib[i];
        }
    }
    return fib_ind;
}

void build_dag()
{
    for(int i = 1; i <= n; i++)
        dag[i] = {-1, -1};
    dag[n - 1] = {n, -1};
    for(int i = n - 2; i >= n - max_ind; i--) {
        dag[i] = {i + 1, i + 2};
    }
    int v = n - max_ind - 1;
    auto fib_ind = find_fibsum(k);
    dag[v] = {n - fib_ind[0], -1};
    v--;
    for(int i = 1; i < fib_ind.size(); i++) {
        dag[v] = {n - fib_ind[i], v + 1};
        v--;
    }
    dag[1] = {v + 1, -1};
}

int calc_fib()
{
    fib[1] = 1;
    fib[2] = 2;
    int i = 3;
    while(fib[i - 1] < 1e9) {
        fib[i] = fib[i - 1] + fib[i - 2];
        i++;
    }
    return i - 2;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    cin >> k;
    max_ind = calc_fib();
    build_dag();
    cout << n << "\n";
    for(int i = 1; i <= n; i++) {
        cout << dag[i].first << ' ' << dag[i].second << "\n";
    }

    return 0;
}