def answer(s: str) -> str:
    for i, c in enumerate(s):
        if i % 2 == 0:
            if c == 'L':
                return 'No'
        else:
            if c == 'R':
                return 'No'

    return 'Yes'


def main():
    s = input()
    print(answer(s))


if __name__ == '__main__':
    main() def answer(s: str) -> str:
    for i, c in enumerate(s):
        if i % 2 == 0:
            if c == 'L':
                return 'No'
        else:
            if c == 'R':
                return 'No'

    return 'Yes' answer for i, c in enumerate(s):
        if i % 2 == 0:
            if c == 'L':
                return 'No'
        else:
            if c == 'R':
                return 'No'

     i c enumerate(s) enumerate s if i % 2 == 0:
            if c == 'L':
                return 'No'
        else:
            if c == 'R':
                return 'No'

     i % 2 == 0 i % 2 i 2 0 if c == 'L':
                return 'No'
         c == 'L' c 'L' return 'No' 'No' if c == 'R':
                return 'No'

     c == 'R' c 'R' return 'No' 'No' return 'Yes' 'Yes' s: str s def main():
    s = input()
    print(answer(s)) main s = input() s input() input print(answer(s)) print answer(s) answer s if __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main def answer(s: str) -> str:
    for i, c in enumerate(s):
        if i % 2 == 0:
            if c == 'L':
                return 'No'
        else:
            if c == 'R':
                return 'No'

    return 'Yes' def answer(s: str) -> str:
    for i, c in enumerate(s):
        if i % 2 == 0:
            if c == 'L':
                return 'No'
        else:
            if c == 'R':
                return 'No'

    return 'Yes' answer def main():
    s = input()
    print(answer(s)) def main():
    s = input()
    print(answer(s)) main
def answer(s: str) -> str:
    for i, c in enumerate(s):
        if i % 2 == 0:
            if c == 'L':
                return 'No'
        else:
            if c == 'R':
                return 'No'

    return 'Yes'


def main():
    s = input()
    print(answer(s))


if __name__ == '__main__':
    main()