def solve():
    s = input()
    if 'L' in s[::2]:
        print('No')
    elif 'R' in s[1::2]:
        print('No')
    else:
        print('Yes')


if __name__ == '__main__':
    solve() def solve():
    s = input()
    if 'L' in s[::2]:
        print('No')
    elif 'R' in s[1::2]:
        print('No')
    else:
        print('Yes') solve s = input() s input() input if 'L' in s[::2]:
        print('No')
    elif 'R' in s[1::2]:
        print('No')
    else:
        print('Yes') 'L' in s[::2] 'L' s[::2] s ::2 2 print('No') print 'No' elif 'R' in s[1::2]:
        print('No')
     'R' in s[1::2] 'R' s[1::2] s 1::2 1 2 print('No') print 'No' print('Yes') print 'Yes' if __name__ == '__main__':
    solve() __name__ == '__main__' __name__ '__main__' solve() solve def solve():
    s = input()
    if 'L' in s[::2]:
        print('No')
    elif 'R' in s[1::2]:
        print('No')
    else:
        print('Yes') def solve():
    s = input()
    if 'L' in s[::2]:
        print('No')
    elif 'R' in s[1::2]:
        print('No')
    else:
        print('Yes') solve
def solve():
    s = input()
    if 'L' in s[::2]:
        print('No')
    elif 'R' in s[1::2]:
        print('No')
    else:
        print('Yes')


if __name__ == '__main__':
    solve()
