import sys
s=input()
for i in range(len(s)):
    if i%2==0 and "L" in s[i]:
        print("No")
        sys.exit()
    elif i%2==1 and "R" in s[i]:
        print("No")
        sys.exit()
print("Yes") import sys sys s=input() s input() input for i in range(len(s)):
    if i%2==0 and "L" in s[i]:
        print("No")
        sys.exit()
    elif i%2==1 and "R" in s[i]:
        print("No")
        sys.exit() i range(len(s)) range len(s) len s if i%2==0 and "L" in s[i]:
        print("No")
        sys.exit()
    elif i%2==1 and "R" in s[i]:
        print("No")
        sys.exit() i%2==0 and "L" in s[i] i%2==0 i%2 i 2 0 "L" in s[i] "L" s[i] s i print("No") print "No" sys.exit() sys.exit sys exit elif i%2==1 and "R" in s[i]:
        print("No")
        sys.exit() i%2==1 and "R" in s[i] i%2==1 i%2 i 2 1 "R" in s[i] "R" s[i] s i 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(len(s)):
    if i%2==0 and "L" in s[i]:
        print("No")
        sys.exit()
    elif i%2==1 and "R" in s[i]:
        print("No")
        sys.exit()
print("Yes")