#include <bits/stdc++.h>
using namespace std;

int main() {
  int n; cin >> n;
  int i = 0;
  int ans = 0;
  int x = 1, y = 1;
  while(ans == 0) {
    if (i % 2) {
      cout << "D" << endl;
    } else {
      cout << "R" << endl;
    }
    cin >> ans;
    i++;
  }
  return 0;
}