#include <bits/stdc++.h>
using namespace std;
vector<pair<int, int>> adj[2 * 300005 + 10];
int vis[2 * 300005 + 10], baatil[2 * 300005 + 10];
int ans[2 * 300005 + 10];
void dfs(int n, int x = 0) {
  vis[n] = 1;
  while (adj[n].size()) {
    auto cv = adj[n].back();
    adj[n].pop_back();
    if (baatil[cv.second]) continue;
    baatil[cv.second] = 1;
    ans[cv.second] = x;
    dfs(cv.first, !x);
  }
}
void solve() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    int x, y;
    cin >> x >> y;
    x = 2 * x;
    y = 2 * y + 1;
    adj[x].push_back({y, i});
    adj[y].push_back({x, i});
  }
  int edge = n;
  for (int i = 0; i < 2 * 300005; i++) {
    if (adj[i].size() & 1) {
      adj[i].push_back({2 * 300005 + ((i + 1) & 1), edge});
      adj[2 * 300005 + ((i + 1) & 1)].push_back({i, edge++});
    }
  }
  if (adj[2 * 300005].size() & 1) {
    adj[2 * 300005].push_back({2 * 300005 + 1, edge});
    adj[2 * 300005 + 1].push_back({2 * 300005, edge++});
  }
  for (int i = 0; i < 2 * 300005; i++) {
    if (!vis[i]) dfs(i);
  }
  for (int i = 0; i < n; i++) cout << (ans[i] ? "b" : "r");
  cout << '\n';
}
int32_t main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int t = 1;
  while (t--) solve();
  return 0;
}
