def main():
    s = input()
    nagasa = len(s)

    for i in range(nagasa):
        if i % 2 == 0 and s[i] == "L":
            print("No")
            exit()
        elif i % 2 != 0 and s[i] == "R":
            print("No")
            exit()
    print("Yes")

    
    
    
if __name__ == "__main__":
    main() def main():
    s = input()
    nagasa = len(s)

    for i in range(nagasa):
        if i % 2 == 0 and s[i] == "L":
            print("No")
            exit()
        elif i % 2 != 0 and s[i] == "R":
            print("No")
            exit()
    print("Yes")

    
    
     main s = input() s input() input nagasa = len(s) nagasa len(s) len s for i in range(nagasa):
        if i % 2 == 0 and s[i] == "L":
            print("No")
            exit()
        elif i % 2 != 0 and s[i] == "R":
            print("No")
            exit()
     i range(nagasa) range nagasa if i % 2 == 0 and s[i] == "L":
            print("No")
            exit()
        elif i % 2 != 0 and s[i] == "R":
            print("No")
            exit()
     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" exit() exit elif i % 2 != 0 and s[i] == "R":
            print("No")
            exit()
     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" exit() exit print("Yes") print "Yes" if __name__ == "__main__":
    main() __name__ == "__main__" __name__ "__main__" main() main def main():
    s = input()
    nagasa = len(s)

    for i in range(nagasa):
        if i % 2 == 0 and s[i] == "L":
            print("No")
            exit()
        elif i % 2 != 0 and s[i] == "R":
            print("No")
            exit()
    print("Yes")

    
    
     def main():
    s = input()
    nagasa = len(s)

    for i in range(nagasa):
        if i % 2 == 0 and s[i] == "L":
            print("No")
            exit()
        elif i % 2 != 0 and s[i] == "R":
            print("No")
            exit()
    print("Yes")

    
    
     main
def main():
    s = input()
    nagasa = len(s)

    for i in range(nagasa):
        if i % 2 == 0 and s[i] == "L":
            print("No")
            exit()
        elif i % 2 != 0 and s[i] == "R":
            print("No")
            exit()
    print("Yes")

    
    
    
if __name__ == "__main__":
    main()
