import sys

S = input()

def check():
  for i in range(len(S)) :
    if i%2!=0 and S[i]=="R" :
      print("No")
      sys.exit(0)
    elif i%2==0 and S[i]=="L" :
      print("No")
      sys.exit(0)
check()
print("Yes")
sys.exit(0) import sys sys S = input() S input() input def check():
  for i in range(len(S)) :
    if i%2!=0 and S[i]=="R" :
      print("No")
      sys.exit(0)
    elif i%2==0 and S[i]=="L" :
      print("No")
      sys.exit(0) check for i in range(len(S)) :
    if i%2!=0 and S[i]=="R" :
      print("No")
      sys.exit(0)
    elif i%2==0 and S[i]=="L" :
      print("No")
      sys.exit(0) i range(len(S)) range len(S) len S if i%2!=0 and S[i]=="R" :
      print("No")
      sys.exit(0)
    elif i%2==0 and S[i]=="L" :
      print("No")
      sys.exit(0) i%2!=0 and S[i]=="R" i%2!=0 i%2 i 2 0 S[i]=="R" S[i] S i "R" print("No") print "No" sys.exit(0) sys.exit sys exit 0 elif i%2==0 and S[i]=="L" :
      print("No")
      sys.exit(0) i%2==0 and S[i]=="L" i%2==0 i%2 i 2 0 S[i]=="L" S[i] S i "L" print("No") print "No" sys.exit(0) sys.exit sys exit 0 check() check print("Yes") print "Yes" sys.exit(0) sys.exit sys exit 0 S = input() input() S def check():
  for i in range(len(S)) :
    if i%2!=0 and S[i]=="R" :
      print("No")
      sys.exit(0)
    elif i%2==0 and S[i]=="L" :
      print("No")
      sys.exit(0) def check():
  for i in range(len(S)) :
    if i%2!=0 and S[i]=="R" :
      print("No")
      sys.exit(0)
    elif i%2==0 and S[i]=="L" :
      print("No")
      sys.exit(0) check
import sys

S = input()

def check():
  for i in range(len(S)) :
    if i%2!=0 and S[i]=="R" :
      print("No")
      sys.exit(0)
    elif i%2==0 and S[i]=="L" :
      print("No")
      sys.exit(0)
check()
print("Yes")
sys.exit(0)