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#include <bits/stdc++.h>

#define fi first
#define se second
#define pb push_back
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int maxn = 2005;

vector<int> graph[105];

int main()
{
    ios_base::sync_with_stdio(0);
    
    int k;
    cin >> k;
    
    int last = 100;
    for (int i = 0; i < 30; i++) {
        graph[last - 1].push_back(last);
        graph[last - 2].push_back(last - 1);
        graph[last - 2].push_back(last);

        last -= 2;
    }

    int cur = 1;
    int pot = 0;
    while (k > 0) {
        if (k % 2 == 1) {
            graph[cur].push_back(100 - pot * 2);
            graph[cur].push_back(cur + 1);
            cur++;
        }

        k /= 2;
        pot++;
    }


    cout << 100 << "\n";

    for (int i = 1; i <= 100; i++) {
        assert(graph[i].size() <= 2);

        if (graph[i].size() == 0) cout << "-1 -1\n";
        if (graph[i].size() == 1) cout << graph[i][0] << " -1\n";
        if (graph[i].size() == 2) cout << graph[i][0] << " " << graph[i][1] << "\n";
    }

    return 0;
}