#include <bits/stdc++.h>
using namespace std;
int vis[200005], p[200005], q[200005];
vector<int> e[200005];
void dfs(int u, int c) {
  vis[u] = c;
  for (auto v : e[u])
    if (vis[v] == -1) dfs(v, c ^ 1);
}
int main() {
  memset(vis, -1, sizeof(vis));
  int n;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    int x, y;
    cin >> x >> y;
    if (p[x]) {
      e[i].push_back(p[x]);
      e[p[x]].push_back(i);
      p[x] = 0;
    } else
      p[x] = i;
    if (q[y]) {
      e[i].push_back(q[y]);
      e[q[y]].push_back(i);
      q[y] = 0;
    } else
      q[y] = i;
  }
  for (int i = 1; i <= n; i++)
    if (vis[i] == -1) dfs(i, 0);
  for (int i = 1; i <= n; i++)
    if (vis[i])
      cout << 'r';
    else
      cout << 'b';
  return 0;
}
