function Main(input) {
	var data = input.split("\n")
	input = data[0]
	var answer = true;
    for(var i =0; i<data[0].length;i++){
    	if(i%2==1 && data[0][i] == "R"){
    		answer = false;
    	}else if(i%2==0 && data[0][i] == "L"){
    		answer = false;
    	}
    }
    console.log((answer)?"Yes":"No")
}
 
// Don't edit this line!
Main(require("fs").readFileSync("/dev/stdin", "utf8"));