let s=readLine()!
var S=Array(s)
var count=1
var k=0
for x in S{
  if count%2==1{
    if x == "L"{
      k=1
    }
  }else{
    if x == "R"{
      k=1
    }
  }
  count+=1
}
if k==1{
  print("No")
}else{
  print("Yes")
}
    