#include <bits/stdc++.h>
using namespace std;
int N;
int X[200005], Y[200005];
char V[200005];
vector<int> con[200005];
void dfs(int n, char c) {
  if (V[n]) return;
  V[n] = c;
  for (int t : con[n]) dfs(t, 'b' + 'r' - c);
}
int main() {
  scanf("%d", &N);
  for (int i = 1; i <= N; i++) {
    int x, y;
    scanf("%d%d", &x, &y);
    if (X[x]) {
      con[i].push_back(X[x]);
      con[X[x]].push_back(i);
      X[x] = 0;
    } else
      X[x] = i;
    if (Y[y]) {
      con[i].push_back(Y[y]);
      con[Y[y]].push_back(i);
      Y[y] = 0;
    } else
      Y[y] = i;
  }
  for (int i = 1; i <= N; i++) {
    dfs(i, 'b');
    printf("%c", V[i]);
  }
  puts("");
}
