#include <bits/stdc++.h>
using namespace std;
long long const MAX = 4e5 + 5;
void f(long long n, long long cur,
       vector<vector<pair<long long, long long>>>& g, long long num,
       vector<long long>& ans) {
  while (g[cur].size() > 0) {
    auto ed = g[cur].back();
    if (ans[ed.second] >= 0) {
      g[cur].pop_back();
    } else {
      ans[ed.second] = num;
      g[cur].pop_back();
      f(n, ed.first, g, (num + 1) % 2, ans);
      break;
    }
  }
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  long long n;
  cin >> n;
  vector<vector<pair<long long, long long>>> g(
      MAX, vector<pair<long long, long long>>());
  vector<long long> ans(n + 3, -1);
  for (long long i = 1; i <= n; i++) {
    long long x, y;
    cin >> x >> y;
    y += MAX / 2;
    g[x].push_back({y, i});
    g[y].push_back({x, i});
  }
  for (long long i = 1; i <= MAX - 1; i++) {
    while (g[i].size() > 0) {
      auto x = g[i].back();
      if (ans[x.second] == -1) {
        ans[x.second] = 0;
        g[i].pop_back();
        f(n, i, g, 1, ans);
        f(n, x.first, g, 1, ans);
      } else {
        g[i].pop_back();
      }
    }
  }
  for (long long i = 1; i <= n; i++) {
    if (ans[i] == 1) {
      cout << 'r';
    } else {
      cout << 'b';
    }
  }
  cout << endl;
}
