#include <bits/stdc++.h>

#include <atcoder/all>
using namespace std;
using i32 = int;
using u32 = unsigned int;
using i64 = long long;
using u64 = unsigned long long;
#define FAST_IO                \
  ios::sync_with_stdio(false); \
  cin.tie(0);
const i64 INF = 1001001001001001001;
using Modint = atcoder::static_modint<998244353>;

int ask(char c) {
  cout << c << endl;
  int x;
  cin >> x;
  if (x != 0) {
    exit(0);
  }
  return x;
}

int main() {
  FAST_IO

  int N;
  cin >> N;


  for (int i = 0; i < N * 2; i ++) {
    if (i % 2 == 0) {
      ask('D');
    } else {
      ask('R');
    }
  }

}