#include <bits/stdc++.h>
using namespace std;
const int N = 2e5, M = 1e6 + 10;
int head[M], ver[M], nxt[M], vis[M], tot = 1;
int n, x, y, du[M], st[M], top;
void add(int u, int v) { ver[++tot] = v, nxt[tot] = head[u], head[u] = tot; }
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) {
    scanf("%d%d", &x, &y);
    y += N;
    add(x, y), add(y, x);
    du[x]++, du[y]++;
  }
  for (int i = 1; i < M; i++)
    if (du[i] & 1) add(0, i), add(i, 0);
  for (int be = 0; be < M; be++) {
    if (!head[be]) continue;
    st[++top] = be;
    while (top > 0) {
      int u = st[top];
      int i = head[u];
      while (i && vis[i]) i = nxt[i];
      head[u] = i;
      if (i) {
        vis[i] = 1, vis[i ^ 1] = 2;
        st[++top] = ver[i];
        head[u] = nxt[i];
      } else
        top--;
    }
  }
  for (int i = 2; i <= n * 2; i += 2)
    if (vis[i] & 1)
      printf("b");
    else
      printf("r");
  return 0;
}
