#include <bits/stdc++.h>
using namespace std;
int main(){
  int N;
  cin >> N;
  int a = 0;
  while (true){
    if (a == 0){
      cout << 'D' << endl;
    } else {
      cout << 'R' << endl;
    }
    a = a ^ 1;
    int v;
    cin >> v;
    if (v == 1){
      break;
    }
  }
}