BACKJOON9019.py

#DSLR

import sys
from typing import Deque

enter = sys.stdin.readline

t = int(enter())
final = []
for _ in range(t):
    a, b = map(int, enter().split())
    print(a, b)
    cmd = [(-1, 0) for _ in range(10000)]
    queue = Deque()
    queue.append(a)
    flag = False

    while True:
        print("o")
        a = queue.popleft()
        count = cmd[a][1]
        for i in range(4):
            if i == 0:
                d = a * 2
                if d > 10000:
                    d -= 10000
                    if cmd[d] == -1:
                        cmd[d] = ("D", count+1)
                        if b == d:
                            flag = True
                            break
                        queue.append(d)
                else:
                    if cmd[d] == -1:
                        cmd[d] = ("D", count+1)
                        if b == d:
                            flag = True
                            break
                        queue.append(d)
            elif i == 1:
                if a == 0:
                    if cmd[9999] == -1:
                        cmd[9999] = ("S", count+1)
                        if b == 9999:
                            flag = True
                            break
                        queue.append(9999)
                else:
                    if cmd[a-1] == -1:
                        cmd[a-1] = ("S", count+1)
                        if b == a - 1:
                            flag = True
                            break
                        queue.append(a-1)
            else:
                d1 = a // 1000
                d2 = (a - d1 * 1000) // 100
                d3 = (a - d1* 1000 - d2 * 100) // 10
                d4 = a % 10
                if i == 2:
                    l = ((d2 * 10 + d3) * 10 + d4) * 10 + d1
                    if cmd[l] == -1:
                        cmd[l] = ("L", count+1)
                        if b == l:
                            flag = True
                            break
                        queue.append(l)
                else:
                    r = ((d4 * 10 + d1) * 10 + d2) * 10 + d3
                    if cmd[r] == -1:
                        cmd[r] = ("R", count + 1)
                        if b == r:
                            flag = True
                            break
                        queue.append(r)

        if flag:
            middle = []
            for i in range(10000):
                if cmd[i][0] == -1:
                    continue
                middle.append(cmd[i])
            middle = sorted(middle, key=lambda x: x[1])
            command = ""
            for i in range(len(middle)):
                command += str(middle[i][0])
            final.append(command)
            break

print("\n".join(final))