#include <bits/stdc++.h>
using namespace std;
const int INF = 1000000000;
const int dir_4[4][2] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};
const int dir_8[8][2] = {{1, 0},  {1, 1},   {0, 1},  {-1, 1},
                         {-1, 0}, {-1, -1}, {0, -1}, {1, -1}};
vector<int> G[200010];
int color[200010];
void dfs(int v, int t) {
  color[v] = t;
  for (int i = 0; i < G[v].size(); i++) {
    if (color[G[v][i]] == 0) dfs(G[v][i], 3 - t);
  }
}
int main() {
  static int n;
  static int x[200010], y[200010];
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d%d", &x[i], &y[i]);
  }
  static vector<int> h[200010], w[200010];
  for (int i = 0; i < n; i++) {
    h[x[i]].push_back(i);
    w[y[i]].push_back(i);
  }
  for (int i = 0; i < 200010; i++) {
    for (int j = 0; j + 1 < h[i].size(); j += 2) {
      G[h[i][j]].push_back(h[i][j + 1]);
      G[h[i][j + 1]].push_back(h[i][j]);
    }
    for (int j = 0; j + 1 < w[i].size(); j += 2) {
      G[w[i][j]].push_back(w[i][j + 1]);
      G[w[i][j + 1]].push_back(w[i][j]);
    }
  }
  for (int i = 0; i < 200010; i++) {
    color[i] = 0;
  }
  for (int i = 0; i < n; i++) {
    if (color[i] == 0) {
      dfs(i, 1);
    }
    printf("%c", (color[i] == 1) ? 'b' : 'r');
  }
}
