#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std; 
using namespace atcoder;
using mint = modint998244353;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define length size()
#define __STDCPP_FLOAT128_T__
#define Real1024 float128_t
#define int long long
#define ll long long
#define ALL(v) (v).begin(), (v).end()
constexpr ll inf = 1001001001001001001ll;
constexpr ll mod = /* 1000000007*/ 998244353;
constexpr double pi = 3.141592653589793;

//小数出力
//cout << setprecision(12);
//max
template< typename T1, typename T2 >
inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }
//min
template< typename T1, typename T2 >
inline bool chmin(T1 &a, T2 b) { return a > b && (a = b, true); }
//print
void print() { cout << '\n'; }
template<typename T>
void print(const T &t) { cout << t << '\n'; }
template<typename Head, typename... Tail>
void print(const Head &head, const Tail &... tail) {
    cout << head << ' ';
    print(tail...);
}
//join
template<typename T> string join(vector<T> &vec ,const string &sp){
    int si = vec.length;
    if(si==0){
        return "";
    }else{
        stringstream ss;
        rep(i,si-1){
            ss << vec[i] << sp;
        }
        ss << vec[si - 1];
        return ss.str();
    }
}
bool in_range(int l,int x,int r){//閉区間
  return (l <= x ) && (x <= r);
}
int div_ceil(int x,int y){
  return (x+y-1)/y;
}
int blood(char x,char y){
  if(x == 'O' && y == 'O') return 3;
  if((x == 'A' && y == 'B') || (x == 'B' && y == 'A')) return 2;
  if(x == 'A' || y == 'A') return 0;
  return 1;
}
//Template End
 vector<pair<int,int>> p_fact(int N) {
     vector<pair<int,int>> res;
     for (int a = 2; a * a <= N; ++a) {
         if (N % a != 0) continue;
         int ex = 0; // 指数
 
         // 割れる限り割り続ける
         while (N % a == 0) {
             ++ex;
             N /= a;
         }
 
         // その結果を push
         res.push_back({a, ex});
     }
 
     // 最後に残った数について
     if (N != 1) res.push_back({N, 1});
     return res;
 }
void one(){
  cout << 2 << endl;
  cout << 1 << " " << 2 << endl;
  cout << "b g" << endl;
}
signed main(void){
  int x;
  cin >> x;
  if(x == 1){
    one();
    return 0;
  }
  auto f = p_fact(x);
  int b = 0;
  int g = 0;
  int kkkk = f.size();
  rep(i,kkkk){
    if(f[i].first == 2){
      b += (f[i].second/2)+f[i].second%2;
      g += f[i].first*f[i].second;
      //cout << b << " " <<g << endl;
      int tmp = (f[i].second/2);
      f[i].second-=tmp*2;
      f.push_back({4,tmp});
    }else{
      b += f[i].second;
      g += f[i].first*f[i].second;
    }
  }
  if(b+g > 200000){
    cout << -1 << endl;
    return 0;
  }
  cout << b+g << endl;
  int b_cnt = 1;
  int g_cnt = b+1;
  int edcnt = 0;
  rep(i,f.size()){
    rep(j,f[i].second){
      rep(k,f[i].first){
        cout << b_cnt << " " << g_cnt << endl;
        g_cnt++;
        edcnt++;
      }
      b_cnt++;
      if(b_cnt != b+1){
        cout << b_cnt-1 << " " << b_cnt << endl;
        edcnt++;
      }
    }
  }
  if(edcnt != b+g-1) edcnt = edcnt/0;
  rep(i,b+g-1){
    if(i < b) cout << "b ";
    else cout << "g ";
  }
  cout << "g" << endl;
}