#include <bits/stdc++.h>
using namespace std;
const int N = 500005;
int n, m;
struct node {
  int y, nxt;
} e[2 * N];
int h[N], c = 1, vis[N], ans[N][2];
void add(int x, int y) {
  e[++c] = (node){y, h[x]};
  h[x] = c;
  e[++c] = (node){x, h[y]};
  h[y] = c;
}
void dfs(int x, int y) {
  if (vis[x]) return;
  vis[x] = y;
  for (int i = h[x]; i; i = e[i].nxt) dfs(e[i].y, 1 ^ y);
}
int main() {
  scanf("%d", &n);
  for (int i = 1, x, y; i <= n; i++) {
    scanf("%d%d", &x, &y);
    if (ans[x][0])
      add(ans[x][0], i), ans[x][0] = 0;
    else
      ans[x][0] = i;
    if (ans[y][1])
      add(ans[y][1], i), ans[y][1] = 0;
    else
      ans[y][1] = i;
  }
  for (int i = 1; i <= n; i++) {
    dfs(i, 0);
    if (vis[i])
      putchar('r');
    else
      putchar('b');
  }
  return 0;
}
