#include <iostream>
#include <vector>
#include <cstring>
#include <functional>

class GraphColorizer {
private:
    static const int MAX_POINTS = 200010;
    
    struct Edge {
        int to, next;
    };

    int n;
    std::vector<int> head;
    std::vector<Edge> edges;
    std::vector<std::vector<int>> last;
    std::vector<int> color;

    void add_edge(int u, int v) {
        edges.push_back({v, head[u]});
        head[u] = edges.size() - 1;
    }

    void dfs_color(int v) {
        for (int i = head[v]; i != -1; i = edges[i].next) {
            int u = edges[i].to;
            if (color[u] == -1) {
                color[u] = color[v] ^ 1;
                dfs_color(u);
            }
        }
    }

public:
    GraphColorizer() : head(MAX_POINTS, -1), last(2, std::vector<int>(MAX_POINTS)), color(MAX_POINTS, -1) {}

    void read_input() {
        std::cin >> n;
        for (int i = 1; i <= n; ++i) {
            int x, y;
            std::cin >> x >> y;
            
            auto connect = [&](int dim, int coord) {
                if (last[dim][coord]) {
                    add_edge(last[dim][coord], i);
                    add_edge(i, last[dim][coord]);
                    last[dim][coord] = 0;
                } else {
                    last[dim][coord] = i;
                }
            };

            connect(0, x);
            connect(1, y);
        }
    }

    void solve() {
        for (int i = 1; i <= n; ++i) {
            if (color[i] == -1) {
                color[i] = 0;
                dfs_color(i);
            }
        }
    }

    void print_result() {
        for (int i = 1; i <= n; ++i) {
            std::cout << (color[i] ? 'r' : 'b');
        }
        std::cout << std::endl;
    }
};

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    GraphColorizer colorizer;
    colorizer.read_input();
    colorizer.solve();
    colorizer.print_result();

    return 0;
}