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#include <iostream>
#include <vector>
#include <algorithm>
#include <stack>

using namespace std;

#define MF 44

vector<int> fibb(MF+1);


struct node {
    int l, r;
    node(int a,int b): l(a), r(b) { }

    void print_rev(int n) {
        if (l == -1) cout << l; else cout  << (n-l+1);
        cout << ' ';
        if (r == -1) cout << r; else cout  << (n-r+1);
        cout << '\n';
    }


};

void fill_fib() {
        fibb[1] = 1;
        fibb[2] = 1;
        for (int k=3;k<=MF;k++) {
            fibb[k] = fibb[k-1] + fibb[k-2];
            //cout << k << " " << fibb[k] << '\n';
        }
}

stack<int> podziel_fibb(int k) {
    stack<int> res;
    int j = MF;
    vector<int> t;
    while (k > 0) {
        while (fibb[j] > k) j--;
        k -= fibb[j];
        //cout << fibb[j] << " (" << j << ") ";
        t.push_back(j);
    }

    //cout << '\n';
    for(int i=t.size()-1;i>=0;i--) res.push(t[i]);
    return res;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;

    if (n == 1) {
        cout << "2\n2 -1\n-1 -1\n";
        return 0;
    }

    fill_fib();


    stack<int> podzial = podziel_fibb(n);
    int mfb = podzial.top();
    //cout << "mfb=" << mfb << "\n";
    vector<node> sol;
    sol.push_back(node(-1,-1));
    sol.push_back(node(1,-1));
    int z = 3;
    while(z <= mfb) {
        sol.push_back(node(z-1,z-2));
        z++;
    }


    int k = mfb;
    while(podzial.size() > 1) {
        int a = podzial.top(); podzial.pop();
        int b = podzial.top(); podzial.pop();
        k++;
        podzial.push(k);
        node q(a,b);
        sol.push_back(q);
    }
    node q(podzial.top(),-1);
    sol.push_back(q);

    cout << sol.size() << '\n';
    for (int i=sol.size()-1;i>=0;i--) {
        sol[i].print_rev(sol.size());
    } 


}