#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2e5 + 5;
vector<pair<int, int> > g[2 * MAXN];
int cl[2 * MAXN];
int deg[2 * MAXN];
void dfs(int v, int color) {
  while (!g[v].empty()) {
    int to = g[v].back().first;
    int id = g[v].back().second;
    g[v].pop_back();
    if (cl[id]) continue;
    deg[to]--;
    deg[v]--;
    cl[id] = color;
    dfs(to, 3 - color);
    break;
  }
}
void solve() {
  int n;
  scanf("%d", &n);
  int x, y;
  for (int i = 0; i < n; i++) {
    scanf("%d%d", &x, &y);
    g[x].push_back(make_pair(MAXN + y, i));
    g[MAXN + y].push_back(make_pair(x, i));
    deg[x]++;
    deg[y + MAXN]++;
  }
  for (int i = 1; i < 2 * MAXN; i++) {
    if (deg[i] <= 0) continue;
    if (deg[i] & 1) {
      dfs(i, 1);
    }
  }
  for (int i = 1; i < 2 * MAXN; i++) {
    if (deg[i] <= 0) continue;
    if (!cl[i]) {
      dfs(i, 2);
    }
  }
  for (int i = 0; i < n; i++) {
    if (cl[i] == 1)
      printf("r");
    else
      printf("b");
  }
}
int main() {
  int t = 1;
  while (t--) {
    solve();
  }
  return 0;
}
