#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:16000000")
using namespace std;
const int Maxm = 200000;
const int Maxn = 400005;
int n;
set<pair<int, int> > neigh[Maxn];
char res[Maxn];
void Solve(int v, bool cur) {
  if (neigh[v].size()) {
    pair<int, int> u = *neigh[v].begin();
    neigh[v].erase(u);
    neigh[u.first].erase(pair<int, int>(v, u.second));
    res[u.second] = cur ? 'r' : 'b';
    cur = !cur;
    Solve(u.first, cur);
  }
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    int x, y;
    scanf("%d %d", &x, &y);
    y += Maxm;
    neigh[x].insert(pair<int, int>(y, i));
    neigh[y].insert(pair<int, int>(x, i));
  }
  for (int i = 0; i < Maxn; i++)
    if (neigh[i].size() % 2) Solve(i, false);
  for (int i = 0; i < Maxn; i++)
    while (neigh[i].size()) Solve(i, false);
  for (int i = 0; i < n; i++) printf("%c", res[i]);
  printf("\n");
  return 0;
}
