#include<bits/stdc++.h>
using namespace std;
using ll=long long;
constexpr int MOD=998244353;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep2(i,l,r) for(int i=(l);i<(int)(r);i++)
#define all(v) v.begin(),v.end()

constexpr int MAX_D=200000;
int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  ll X;
  cin>>X;
  vector d(0,0ll);
  rep2(i,3,MAX_D){
    while(X%i==0){
      d.push_back(i);
      X/=i;
    }
  }
  if(X!=1)d.push_back(X);
  if(d.empty())d.push_back(1);
  ll s=accumulate(all(d),0ll);
  if(s+d.size()>MAX_D){
    cout<<"-1\n";
    return 0;
  }
  cout<<s+d.size()<<'\n';
  rep(i,d.size()-1){
    cout<<i+1<<' '<<i+2<<'\n';
  }
  int cnt=d.size();
  rep(i,d.size()){
    rep(j,d[i]){
      cnt++;
      cout<<i+1<<' '<<cnt<<'\n';
    }
  }
  rep(i,d.size()){
    if(i)cout<<' ';
    cout<<'b';
  }
  rep(i,s){
    cout<<" g";
  }
  cout<<'\n';
}