[Link] https://www.acmicpc.net/problem/9019
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/*
took too long for debugging this error
StringBuilder sb1 = new StringBuilder();
StringBuilder sb2 = new StringBuilder();
sb1.append('c');
sb2.append('c');
sb1.toString().equals(sb2.toString()) => true
char[] ch = new char[3];
sb2.append(ch[0]);
sb1.toString().equals(sb2.toString()) => false
*/
import java.util.*;
import java.io.*;
public class Main {
static BufferedReader br;
static int max = 0, maxIdx = 0;
public static void main(String[] args) throws IOException {
StringBuilder sb1 = new StringBuilder();
StringBuilder sb2 = new StringBuilder();
br = new BufferedReader(new InputStreamReader(System.in));
StringBuilder sb = new StringBuilder();
String[] line ;
int t = toi(br.readLine());
for(int iter = 0; iter < t; iter++) {
line = getLine();
int a = toi(line[0]), b = toi(line[1]);
int[] parent = new int[10000];
Arrays.fill(parent, -1);
char[] oper = new char[10000];
Queue<Integer> q = new LinkedList<>();
q.add(a);
parent[a] = -2;
while(!q.isEmpty()) {
int cur = q.poll();
if(cur == b) break;
int db = doublef(cur), leftV = left(cur), rightV = right(cur), deV = decrement(cur);
if(parent[db] == -1) {
parent[db] = cur;
oper[db] = 'D';
q.add(db);
}
if(parent[deV] == -1) {
parent[deV] = cur;
oper[deV] = 'S';
q.add(deV);
}
if(parent[leftV] == -1) {
parent[leftV] = cur;
oper[leftV] = 'L';
q.add(leftV);
}
if(parent[rightV] == -1) {
parent[rightV] = cur;
oper[rightV] = 'R';
q.add(rightV);
}
}
ArrayList<Character> al = new ArrayList<>();
int idx = b;
while(parent[idx] != -2) {
al.add(oper[idx]);
idx = parent[idx];
}
for(int i = al.size() - 1; i >=0; i--) sb.append(al.get(i));
sb.append("\n");
}
print(sb);
}
static int doublef(int n) {
n *= 2;
if(n >= 10000) n-= 10000;
return n;
}
static int decrement(int n) {
return n == 0 ? 9999 : n - 1;
}
static int[] getDigits(int n) {
int d1 = n / 1000;
n-= 1000*d1;
int d2 = n / 100;
n-= 100 * d2;
int d3 = n / 10;
int d4 = n - 10 * d3;
return new int[] { d1, d2, d3, d4 };
}
static int right(int n) {
int[] digits = getDigits(n);
return 1000 * digits[3] + 100 * digits[0] + 10 * digits[1] + digits[2];
}
static int left(int n) {
int[] digits = getDigits(n);
return 1000 * digits[1] + 100 * digits[2] + 10 * digits[3] + digits[0];
}
static int toi(String s) { return Integer.parseInt(s); }
static String[] getLine() throws IOException { return br.readLine().split(" "); }
static <T> void print(T s) { System.out.print(s); }
static <T> void println(T s) { System.out.println(s); }
}