#include <bits/stdc++.h>
using namespace std;
const int maxn = 4e5;
set<pair<int, int> > a[3 * maxn + 1000];
bool ans[3 * maxn + 1000];
void dfs(int x, int col) {
  if (!a[x].size()) return;
  pair<int, int> temp = *a[x].begin();
  int num = temp.second;
  int u = temp.first;
  a[x].erase(pair<int, int>(u, num));
  a[u].erase(pair<int, int>(x, num));
  ans[num] = col;
  dfs(u, 1 - col);
}
int main() {
  ios_base::sync_with_stdio(false);
  int n;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    int u, v;
    cin >> u >> v;
    v += maxn;
    a[u].insert(pair<int, int>(v, i));
    a[v].insert(pair<int, int>(u, i));
  }
  int oo = 8e5 + 100;
  int mm = 8e5 + 50;
  for (int i = 1; i <= maxn; i++) {
    int u = i;
    if (a[u].size() % 2 == 1) {
      a[u].insert(pair<int, int>(oo, 0));
      a[oo].insert(pair<int, int>(u, 0));
    }
    if (a[u + maxn].size() % 2 == 1) {
      a[mm].insert(pair<int, int>(u + maxn, 0));
      a[u + maxn].insert(pair<int, int>(mm, 0));
    }
  }
  if (a[mm].size() % 2 == 1) {
    a[mm].insert(pair<int, int>(oo, 0));
    a[oo].insert(pair<int, int>(mm, 0));
  }
  for (int i = 1; i <= maxn; i++)
    while (a[i].size()) dfs(i, 0);
  for (int i = 1; i <= n; i++) {
    if (ans[i])
      cout << 'r';
    else
      cout << 'b';
  }
  return 0;
}
