import bisect,collections,copy,heapq,itertools,math,string
import sys
def S(): return sys.stdin.readline().rstrip()
def M(): return map(int,sys.stdin.readline().rstrip().split())
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LS(): return list(sys.stdin.readline().rstrip().split())
s = S()
ans = 'Yes'
for i in range(len(s)):
    if i%2 == 0:
        if s[i] == 'L':
            ans = 'No'
    else:
        if s[i] == 'R':
            ans = 'No'
print(ans) import bisect,collections,copy,heapq,itertools,math,string bisect collections copy heapq itertools math string import sys sys def S(): return sys.stdin.readline().rstrip() S def M(): return map(int,sys.stdin.readline().rstrip().split()) M def I(): return int(sys.stdin.readline().rstrip()) I def LI(): return list(map(int,sys.stdin.readline().rstrip().split())) LI def LS(): return list(sys.stdin.readline().rstrip().split()) LS s = S() s S() S ans = 'Yes' ans 'Yes' for i in range(len(s)):
    if i%2 == 0:
        if s[i] == 'L':
            ans = 'No'
    else:
        if s[i] == 'R':
            ans = 'No' i range(len(s)) range len(s) len s if i%2 == 0:
        if s[i] == 'L':
            ans = 'No'
    else:
        if s[i] == 'R':
            ans = 'No' i%2 == 0 i%2 i 2 0 if s[i] == 'L':
            ans = 'No'
     s[i] == 'L' s[i] s i 'L' ans = 'No' ans 'No' if s[i] == 'R':
            ans = 'No' s[i] == 'R' s[i] s i 'R' ans = 'No' ans 'No' print(ans) print ans ans = 'No' 'No' ans def M(): return map(int,sys.stdin.readline().rstrip().split()) def M(): return map(int,sys.stdin.readline().rstrip().split()) M s = S() S() s ans = 'No' 'No' ans def I(): return int(sys.stdin.readline().rstrip()) def I(): return int(sys.stdin.readline().rstrip()) I def LI(): return list(map(int,sys.stdin.readline().rstrip().split())) def LI(): return list(map(int,sys.stdin.readline().rstrip().split())) LI def S(): return sys.stdin.readline().rstrip() def S(): return sys.stdin.readline().rstrip() S ans = 'Yes' 'Yes' ans def LS(): return list(sys.stdin.readline().rstrip().split()) def LS(): return list(sys.stdin.readline().rstrip().split()) LS
import bisect,collections,copy,heapq,itertools,math,string
import sys
def S(): return sys.stdin.readline().rstrip()
def M(): return map(int,sys.stdin.readline().rstrip().split())
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LS(): return list(sys.stdin.readline().rstrip().split())
s = S()
ans = 'Yes'
for i in range(len(s)):
    if i%2 == 0:
        if s[i] == 'L':
            ans = 'No'
    else:
        if s[i] == 'R':
            ans = 'No'
print(ans)