#include <bits/stdc++.h>
std::vector<int> g[222222];
int xx[222222];
int yy[222222];
int v[222222];
void dfs(int x, int y) {
  if (v[x]) return;
  int i;
  v[x] = y;
  for (i = 0; i < g[x].size(); i++) dfs(g[x][i], 3 - y);
}
int main() {
  int x, y;
  int i, n;
  scanf("%d", &n);
  for (i = 1; i <= n; i++) {
    scanf("%d%d", &x, &y);
    if (xx[x]) {
      g[i].push_back(xx[x]);
      g[xx[x]].push_back(i);
      xx[x] = 0;
    } else
      xx[x] = i;
    if (yy[y]) {
      g[i].push_back(yy[y]);
      g[yy[y]].push_back(i);
      yy[y] = 0;
    } else
      yy[y] = i;
  }
  for (i = 1; i <= n; i++) {
    dfs(i, 1);
    putchar(v[i] > 1 ? 'b' : 'r');
  }
}
