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#pragma GCC optimize("O3")
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>

#define BOOST ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define FOR(a, b, c) for(int a = b; a < c; ++a)
#define PB push_back
#define MP make_pair
#define INF (int)1e9+7
#define LLINF 2e18+7
#define ALL(a) a.begin(), a.end()
#define SIZE(a) (int)a.size()

typedef unsigned long long ULL;
typedef long long LL;
typedef long double LD;

using namespace std;

//#define DEBUG

vector <vector <int> > graph;

const int PWR = 30;

int main()
{
    #ifndef DEBUG
    BOOST;
    #endif

    int k;
    cin >> k;

    int n = 2 + PWR * 3;
    graph.resize(n + 1);

    for(int i = 0; i < PWR; ++i)
    {
        int v = 1 + 3 * i;

        graph[v].push_back(v + 1);
        graph[v].push_back(v + 2);

        graph[v + 1].push_back(v + 3);
        graph[v + 2].push_back(v + 3);
    }

    FOR(i, 0, PWR + 1)
    {
        if(k & (1 << i))
        {
            graph[1 + 3 * i + 1].push_back(n);
        }
    }

    cout << n << "\n";

    FOR(i, 1, n + 1)
    {
        if(graph[i].size() == 0)
        {
            cout << -1 << " " << -1 << "\n";
        }
        else if(graph[i].size() == 1)
        {
            cout << -1 << " " << graph[i][0] << "\n";
        }
        else
        {     
            cout << graph[i][1] << " " << graph[i][0] << "\n";
        }
    }

    return 0;
}