#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
template <class T>
using vc = vector<T>;
template <class T>
using vvc = vc<vc<T>>;
template <class T>
using vvvc = vc<vvc<T>>;
#define overload5(a, b, c, d, e, name, ...) name
#define overload4(a, b, c, d, name, ...) name
#define overload3(a, b, c, name, ...) name
#define rep1(n) for (ll i = 0; i < n; ++i)
#define rep2(i, n) for (ll i = 0; i < n; ++i)
#define rep3(i, a, b) for (ll i = a; i < b; ++i)
#define rep4(i, a, b, c) for (ll i = a; i < b; i += c)
#define rep(...) overload4(__VA_ARGS__, rep4, rep3, rep2, rep1)(__VA_ARGS__)
#define rrep1(n) for (ll i = n; i--;)
#define rrep2(i, n) for (ll i = n; i--;)
#define rrep3(i, a, b) for (ll i = b; i-- > (a);)
#define rrep(...) \
    overload4(__VA_ARGS__, rrep4, rrep3, rrep2, rrep1)(__VA_ARGS__)
#define each1(i, a) for (auto &&i : a)
#define each2(x, y, a) for (auto &&[x, y] : a)
#define each3(x, y, z, a) for (auto &&[x, y, z] : a)
#define each4(w, x, y, z, a) for (auto &&[w, x, y, z] : a)
#define each(...) \
    overload5(__VA_ARGS__, each4, each3, each2, each1)(__VA_ARGS__)
#define all1(i) begin(i), end(i)
#define all2(i, a) begin(i), begin(i) + a
#define all3(i, a, b) begin(i) + a, begin(i) + b
#define all(...) overload3(__VA_ARGS__, all3, all2, all1)(__VA_ARGS__)
#define rall1(i) rbegin(i), rend(i)
#define rall2(i, a) rbegin(i), rbegin(i) + a
#define rall3(i, a, b) rbegin(i) + a, rbegin(i) + b
#define rall(...) overload3(__VA_ARGS__, rall3, rall2, rall1)(__VA_ARGS__)
template <class T>
bool chmin(T &a, const T &b) {
    if (a <= b) return 0;
    a = b;
    return 1;
}
template <class T>
bool chmax(T &a, const T &b) {
    if (a >= b) return 0;
    a = b;
    return 1;
}
template <class T, class U>
bool chmin(T &a, const U &b) {
    return chmin(a, (T)b);
}
template <class T, class U>
bool chmax(T &a, const U &b) {
    return chmax(a, (T)b);
}
void solve();
int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(20);
    ll t = 1;
    // cin >> t;
    for (int i = 1; i <= t; i++) solve();
    return 0;
}
ll dy[] = {0, 0, 1, 0, -1}, dx[] = {0, 1, 0, -1, 0};
// ll dy[8] = {1, 1, 0, -1, -1, -1, 0, 1}, dx[8] = {0, 1, 1, 1, 0, -1, -1, -1};
void solve() {
    vc<ll> ma = {0};
    rep(i, 1, 1e5 + 10) ma.push_back(ma.back() + (i + 1) / 2);
    ll n;
    cin >> n;
    if (n == 1) {
        cout << 1 << endl << "r" << endl;
        return;
    }
    auto calc = [&](string s) {
        ll res = 0;
        ll cur = 0;
        ll ec = 0, oc = 0;
        for (auto c : s) {
            if (cur == 0)
                ec++;
            else
                oc++;
            if (c == '0') {
                if (cur == 0)
                    res += oc;
                else
                    res += ec;
            } else {
                cur ^= 1;
                if (cur == 0)
                    res += oc;
                else
                    res += ec;
            }
        }
        return res;
    };
    if (n >= 300) {
        ll _n = n - n % 2;
        vc<string> res;
        string s = string(_n, '0');
        s[_n / 2] = '1';
        res.push_back(s);
        s[_n / 2] = '0', s[_n / 2 - 1] = '1';
        res.push_back(s);
        s[_n - 1] = '1';
        res.push_back(s);
        s[_n - 2] = '1';
        res.push_back(s);
        for (int i = _n - 3; i >= _n / 2; i--) {
            s[i] = '1', s[i + 2] = '0';
            res.push_back(s);
            if (res.size() == 100) break;
        }
        if (n % 2 == 1) {
            for (auto &x : res) {
                string x0 = x, x1 = x;
                x0.push_back('0');
                x1.push_back('1');
                if (calc(x0) > calc(x1))
                    x.push_back('0');
                else
                    x.push_back('1');
            }
        }
        cout << ma[n] << endl;
        for (auto x : res) {
            for (auto c : x) cout << (c == '0' ? 'b' : 'r');
            cout << endl;
        }
    } else {
        ll _n = n - n % 2;
        vc<string> res;
        if (_n <= 18) {
            rep(i, 0, 1 << _n) {
                string s;
                rep(j, 0, _n) s.push_back((i >> j & 1) + '0');
                if (calc(s) == ma[_n]) res.push_back(s);
            }
            sort(all(res));
            res.erase(unique(all(res)), res.end());
            while (res.size() > 1000) res.pop_back();
        }
        for (int i = 20; i <= _n; i += 2) {
            vc<string> nres;
            for (auto x : res) {
                rep(j, 4) {
                    string tmp = "00";
                    if (j == 1) tmp = "01";
                    if (j == 2) tmp = "10";
                    if (j == 3) tmp = "11";
                    string nx = x + tmp;
                    if (calc(nx) == ma[i]) nres.push_back(nx);
                    nx = tmp + x;
                    if (calc(nx) == ma[i]) nres.push_back(nx);
                }
            }
            sort(all(nres));
            nres.erase(unique(all(nres)), nres.end());
            while (nres.size() > 1000) nres.pop_back();
            res = nres;
        }
        while (res.size() > 100) res.pop_back();
        if (n % 2 == 1) {
            for (auto &x : res) {
                string x0 = x, x1 = x;
                x0.push_back('0');
                x1.push_back('1');
                if (calc(x0) > calc(x1))
                    x.push_back('0');
                else
                    x.push_back('1');
            }
        }
        cout << ma[n] << endl;
        for (auto x : res) {
            for (auto c : x) cout << (c == '0' ? 'b' : 'r');
            cout << endl;
        }
    }
}