import sys
S = input()
for i in range(0, len(S), +2):
    if S[i] == "L":
        print("No")
        sys.exit()    
if len(S) == 1:
    print("Yes")
    sys.exit()
for i in range(1, len(S), +2):
    if S[i] == "R":
        print("No")
        sys.exit()
print("Yes") import sys sys S = input() S input() input for i in range(0, len(S), +2):
    if S[i] == "L":
        print("No")
        sys.exit()     i range(0, len(S), +2) range 0 len(S) len S +2 2 if S[i] == "L":
        print("No")
        sys.exit()     S[i] == "L" S[i] S i "L" print("No") print "No" sys.exit() sys.exit sys exit if len(S) == 1:
    print("Yes")
    sys.exit() len(S) == 1 len(S) len S 1 print("Yes") print "Yes" sys.exit() sys.exit sys exit for i in range(1, len(S), +2):
    if S[i] == "R":
        print("No")
        sys.exit() i range(1, len(S), +2) range 1 len(S) len S +2 2 if S[i] == "R":
        print("No")
        sys.exit() S[i] == "R" S[i] S i "R" print("No") print "No" sys.exit() sys.exit sys exit print("Yes") print "Yes" S = input() input() S
import sys
S = input()
for i in range(0, len(S), +2):
    if S[i] == "L":
        print("No")
        sys.exit()    
if len(S) == 1:
    print("Yes")
    sys.exit()
for i in range(1, len(S), +2):
    if S[i] == "R":
        print("No")
        sys.exit()
print("Yes")
