#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

int main() {
  int n;
  cin >> n;
  int x = 0;
  while (true) {
    cout << "DR"[x] << endl;
    x = (x + 1) % 2;
    int v;
    cin >> v;
    if (v == 1 || v == -1) break;
  }
  return 0;
}