#include <bits/stdc++.h>
using namespace std;
int v[1000010];
int x[1000010];
int ct;
int al[1000010];
int col[1000010];
int n;
int lstu[1000010];
int lstv[1000010];
inline void add(int u, int V) {
  v[++ct] = V;
  x[ct] = al[u];
  al[u] = ct;
}
inline void dfs(int u, int tw) {
  col[u] = tw;
  for (int i = al[u]; i; i = x[i])
    if (col[v[i]] == -1) dfs(v[i], tw ^ 1);
}
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) col[i] = -1;
  for (int i = 1, x, y; i <= n; i++) {
    scanf("%d%d", &x, &y);
    if (lstu[x]) {
      add(lstu[x], i), add(i, lstu[x]), lstu[x] = 0;
    } else
      lstu[x] = i;
    if (lstv[y]) {
      add(lstv[y], i), add(i, lstv[y]), lstv[y] = 0;
    } else
      lstv[y] = i;
  }
  for (int i = 1; i <= n; i++)
    if (col[i] == -1) dfs(i, 0);
  for (int i = 1; i <= n; i++) putchar((col[i]) ? 'r' : 'b');
  return 0;
}
