#include <bits/stdc++.h>
using namespace std;
template <class T, class T1>
void chkmin(T &x, const T1 &y) {
  return x > y ? x = y, 1 : 0;
}
template <class T, class T1>
void chkmax(T &x, const T1 &y) {
  return x < y ? x = y, 1 : 0;
}
const int MAXN = (1 << 20);
int n;
pair<int, int> a[MAXN];
int main_dir[MAXN];
vector<pair<int, int> > adj[MAXN];
char col[MAXN];
void read() {
  cin >> n;
  for (int i = 0; i < n; i++) cin >> a[i].first >> a[i].second;
}
int deg[MAXN];
void path_dfs(int u) {
  while (!adj[u].empty()) {
    if (col[adj[u].back().second] != 0) {
      adj[u].pop_back();
      continue;
    }
    int i = adj[u].back().second, v = adj[u].back().first;
    adj[u].pop_back();
    col[i] = (main_dir[i] == u) ? 'r' : 'b';
    deg[u] ^= 1, deg[v] ^= 1;
    path_dfs(v);
    return;
  }
}
void solve() {
  for (int i = 0; i < n; i++) {
    int u = a[i].first, v = a[i].second + (int)5e5;
    adj[u].push_back(make_pair(v, i));
    adj[v].push_back(make_pair(u, i));
    main_dir[i] = u;
    deg[u] ^= 1, deg[v] ^= 1;
  }
  for (int i = 1; i < MAXN; i++)
    if (deg[i]) path_dfs(i);
  for (int i = 1; i < MAXN; i++) path_dfs(i);
  for (int i = 0; i < n; i++) cout << col[i];
  cout << '\n';
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  read();
  solve();
  return 0;
}
