#include <bits/stdc++.h>
using namespace std;
const int N = 200050;
const int M = 2 * N;
set<pair<int, int> > E[M];
int col[N];
void SolvePath(int u, int c) {
  if (E[u].size() & 1) {
    int v = E[u].begin()->first;
    int e = E[u].begin()->second;
    col[e] = c;
    E[u].erase(make_pair(v, e));
    E[v].erase(make_pair(u, e));
    SolvePath(v, c ^ 1);
  }
}
void SolveCycle(int u, int c) {
  if (E[u].size()) {
    int v = E[u].begin()->first;
    int e = E[u].begin()->second;
    col[e] = c;
    E[u].erase(make_pair(v, e));
    E[v].erase(make_pair(u, e));
    SolveCycle(v, c ^ 1);
  }
}
int main() {
  int n, i, u, v;
  scanf("%i", &n);
  for (i = 1; i <= n; i++)
    scanf("%i %i", &u, &v), v += N, E[u].insert(make_pair(v, i)),
        E[v].insert(make_pair(u, i));
  for (i = 1; i < M; i++) SolvePath(i, 1);
  for (i = 1; i < M; i++) SolveCycle(i, 1);
  for (i = 1; i <= n; i++) {
    if (col[i])
      printf("r");
    else
      printf("b");
  }
  printf("\n");
  return 0;
}
