#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5 + 5;
const int mod = 1e9 + 7;
const int inf = 1e18 + 500;
pair<int, int> query[maxn];
vector<int> G[5 * maxn], ans;
vector<pair<int, int> > adj[5 * maxn];
bool mark[maxn * 5];
map<pair<int, int>, int> m;
void dfs(int v) {
  while (!adj[v].empty()) {
    int id = adj[v].back().second;
    int u = adj[v].back().first;
    adj[v].pop_back();
    if (!mark[id]) {
      mark[id] = 1;
      dfs(u);
    }
  }
  ans.push_back(v);
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int n, mx = 2e5 + 1000;
  int ali = 3 * maxn + 1000;
  int mam = 3 * maxn + 1001;
  cin >> n;
  string res = "";
  int num = n;
  for (int i = 0; i < n; i++) {
    int u, v;
    cin >> u >> v;
    G[u].push_back(v + mx);
    G[v + mx].push_back(u);
    query[i].first = u;
    query[i].second = v;
    m[make_pair(u, v + mx)] = 0;
    m[make_pair(v + mx, u)] = 0;
    adj[u].push_back(make_pair(v + mx, i));
    adj[v + mx].push_back(make_pair(u, i));
  }
  for (int i = 0; i < n; i++) {
    if (G[query[i].first].size() & 1) {
      G[query[i].first].push_back(ali);
      G[ali].push_back(query[i].first);
      adj[query[i].first].push_back(make_pair(ali, num));
      adj[ali].push_back(make_pair(query[i].first, num));
      num++;
    }
    if (G[query[i].second + mx].size() & 1) {
      G[query[i].second + mx].push_back(mam);
      G[mam].push_back(query[i].second + mx);
      adj[query[i].second + mx].push_back(make_pair(mam, num));
      adj[mam].push_back(make_pair(query[i].second + mx, num));
      num++;
    }
  }
  if (G[ali].size() & 1) {
    G[mam].push_back(ali);
    G[ali].push_back(mam);
    adj[ali].push_back(make_pair(mam, num));
    adj[mam].push_back(make_pair(ali, num));
    num++;
  }
  for (int i = 0; i < maxn; i++)
    if (!mark[i]) dfs(i);
  for (int i = 0; i < ans.size() - 1; i++) {
    if (ans[i] < ali && ans[i + 1] < ali) {
      m[make_pair(ans[i], ans[i + 1])] = 1;
    }
  }
  for (int i = 0; i < n; i++) query[i].second += mx;
  for (int i = 0; i < n; i++) {
    if (m[make_pair(query[i].first, query[i].second)] == 1)
      res += "b";
    else
      res += "r";
  }
  cout << res << endl;
  return 0;
}
