#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using mint = atcoder::static_modint<998244353>;
// using mint = atcoder::static_modint<1000000007>;
using ld = long double;
using ll = long long;
#define mp(a,b) make_pair(a,b)
#define rep(i,s,n) for(int i=s; i<(int)n; i++)
using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vvvvl = vector<vvvl>;
const vector<int> dx{1,0,-1,0},dy{0,1,0,-1};

int main(){
    // ios::sync_with_stdio(false);
    // cin.tie(nullptr);
    int n;cin >> n;
    vector<char> C{'D','R'};
    int t=0;
    while(true){
        cout << C[t] << "\n";
        t^=1;
        int x;cin >> x;
        if(x)return 0;
    }
}