#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#include<atcoder/modint>
using namespace atcoder;
using mint = modint998244353;


void solve() {
    ll X;
    cin>>X;
    vector<bool> P(2e5+10,1);
    P[0]=P[1]=0;
    vector<int> Q;
    if(X==1){
        Q.push_back(1);
    }
    for(int i=0;i<2e5+10;i++){
        if(P[i]){
            for(int j=i*2;j<2e5+10;j+=i)P[j]=0;
            while(X%i==0){
                if(i==2){
                    if(X%4==0){
                        Q.push_back(4);
                        X/=4;
                    }
                    else{
                        Q.push_back(2);
                        X/=2;
                    }
                }
                else{
                    Q.push_back(i);
                    X/=i;
                }
            }
        }
    } 
    if(X!=1){
        cout<<-1<<endl;
        return;
    }
    ll S=Q.size();
    for(int q:Q){
        S+=q;
    }
    if(S>2e5){
        cout<<-1<<endl;
        return;
    }
    cout<<S<<endl;
    int cnt=Q.size();
    for(int i=1;i<Q.size();i++){
        cout<<i<<" "<<i+1<<endl;
        for(int j=0;j<Q[i-1];j++){
            cout<<i<<" "<<cnt+1<<endl;
            cnt++;
        }
    }
    for(int j=0;j<Q.back();j++){
        cout<<Q.size()<<" "<<cnt+1<<endl;
        cnt++;
    }
    for(int i=0;i<S;i++){
        cout<<"gb"[i<Q.size()]<<" \n"[i==S-1];
    }
}

int main() {

    ios::sync_with_stdio(false);
    cin.tie(nullptr);


    // ll T;
    // cin>>T;
    // while(T--)
    solve();
}