#include <bits/stdc++.h>
using namespace std;
int n, x[200001], y[200001], a[200001], b[200001];
int p, q;
set<pair<int, int> > g[2 * 200001];
int deg[2 * 200001];
int cl[200001];
int cnt;
stack<pair<int, int> > s;
void tomau(int u, int mau) {
  while (!g[u].empty()) {
    int v = (*g[u].begin()).first, k = (*g[u].begin()).second;
    cl[k] = mau;
    cnt++;
    g[u].erase(make_pair(v, k));
    deg[u]--;
    g[v].erase(make_pair(u, k));
    deg[v]--;
    u = v;
    mau = 3 - mau;
  }
}
int main() {
  ios::sync_with_stdio(false);
  cin >> n;
  for (int i = 1; i <= n; i++) cin >> x[i] >> y[i];
  for (int i = 1; i <= n; i++) a[i] = x[i];
  sort(a + 1, a + n + 1);
  p = unique(a + 1, a + n + 1) - a - 1;
  for (int i = 1; i <= n; i++) b[i] = y[i];
  sort(b + 1, b + n + 1);
  q = unique(b + 1, b + n + 1) - b - 1;
  for (int i = 1; i <= n; i++) {
    int u = lower_bound(a + 1, a + p + 1, x[i]) - a;
    int v = lower_bound(b + 1, b + q + 1, y[i]) - b;
    g[u].insert(make_pair(v + p, i));
    deg[u]++;
    g[v + p].insert(make_pair(u, i));
    deg[v + p]++;
  }
  fill(cl, cl + n + 1, 0);
  cnt = 0;
  for (int u = 1; u <= p + q; u++) {
    if (deg[u] % 2) tomau(u, 1);
    if (cnt == n) break;
  }
  if (cnt < n)
    for (int u = 1; u <= p + q; u++)
      if (deg[u] > 0 && deg[u] % 2 == 0) {
        tomau(u, 1);
        if (cnt == n) break;
      }
  for (int i = 1; i <= n; i++)
    if (cl[i] == 1)
      printf("b");
    else
      printf("r");
}
