#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5 + 10;
set<int> adj[maxn * 2 + 20];
int ans[maxn], n;
vector<int> ans_eu;
map<pair<int, int>, int> mp;
void find_eu(int v) {
  while (adj[v].size()) {
    int tmp = *adj[v].begin();
    adj[v].erase(tmp);
    adj[tmp].erase(v);
    find_eu(tmp);
  }
  ans_eu.push_back(v);
}
void solve() {
  for (int i = 1, tmp = maxn * 2 + 9; i < maxn * 2 + 10; i++)
    if (adj[i].size() % 2 == 1) adj[tmp].insert(i), adj[i].insert(tmp);
  for (int i = maxn * 2 + 9; i > 0; i--) {
    if (adj[i].size()) {
      ans_eu.clear();
      find_eu(i);
      for (int j = 1; j < ans_eu.size(); j++)
        if (max(ans_eu[j], ans_eu[j - 1]) != maxn * 2 + 9)
          ans[mp[{ans_eu[j], ans_eu[j - 1]}]] = j % 2;
    }
  }
  for (int i = 1; i <= n; i++) cout << (ans[i] ? 'r' : 'b');
  cout << endl;
}
int main() {
  cin >> n;
  for (int i = 1, x, y; i <= n; i++) {
    cin >> x >> y;
    adj[x].insert(y + maxn);
    adj[y + maxn].insert(x);
    mp[{x, y + maxn}] = mp[{y + maxn, x}] = i;
  }
  solve();
  return 0;
}
