#pragma GCC target("avx")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")

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

using std::cin;
using std::cout;

#define rep(i,n) for(int i = 0; i < (int)n; i++)
#define FOR(n) for(int i = 0; i < (int)n; i++)
#define repi(i,a,b) for(int i = (int)a; i < (int)b; i++)
#define all(x) x.begin(),x.end()
//#define mp make_pair
#define vi vector<int>
#define vvi vector<vi>
#define vvvi vector<vvi>
#define vvvvi vector<vvvi>
#define pii pair<int,int>
#define vpii vector<pair<int,int>>

template<typename T>
bool chmax(T &a, const T b) {if(a<b) {a=b; return true;} else {return false;}}
template<typename T>
bool chmin(T &a, const T b) {if(a>b) {a=b; return true;} else {return false;}}

using ll = long long;
using ld = long double;
using ull = unsigned long long;

const ll INF = numeric_limits<long long>::max() / 2;
const ld pi = 3.1415926535897932384626433832795028;
const ll mod = 998244353;
int dx[] = {1, 0, -1, 0, -1, -1, 1, 1};
int dy[] = {0, 1, 0, -1, -1, 1, -1, 1};

#define int long long

void solve() {
    const int MX = 2e5 + 100;
    int x;
    cin >> x;
    if(x == 1) {
        cout << 2 << endl;
        cout << 1 << " " << 2 << endl;
        cout << "b g" << endl;
        return;
    }
    vi facts;
    int sum = 0;
    repi(i, 3, min(MX, x+1)) {
        while(x % i == 0) {
            x /= i;
            facts.emplace_back(i);
            sum += i + 1;
        }
    }
    while(x % 2 == 0) {
        x /= 2;
        facts.emplace_back(2);
        sum += 2 + 1;
    }
    if(sum > 2e5 || x != 1) {
        cout << -1 << endl;
        return;
    }
    const int sz = (int)facts.size();

    cout << sum << endl;
    FOR(sz-1) cout << i+1 << " " << i+2 << endl;
    int cur = (int)facts.size() + 1;
    rep(i, sz) {
        rep(_, facts[i]) {
            cout << i+1 << " " << cur++ << endl;
        }
    }
    FOR(sz) cout << 'b' << " ";
    FOR(sum-sz) cout << 'g' << " ";
    cout << endl;
}

signed main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    solve();
    return 0;
}