function Main(input){
    a=input.split("");
    a.pop()
    var ans=true;
    for(var i=0;i<a.length;i++){
        if(i%2==0&&a[i]=="L")ans=false
        else if(i%2==1&&a[i]=="R")ans=false
    }
    if(ans)console.log("Yes")
    else console.log("No")
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));