function main(input) {                                      
    var S = input.trim();                                   
                                                            
    var unOddFoot = "L";                                    
    var unEvenFoot = "R";                                   
                                                            
    var result = "Yes"                                      
    for(var i = 0; S.length > i; i++) {                     
        if (i % 2 === 0) {                                  
            if (S[i] === unOddFoot) {                       
                result = "No";                              
                break;                                      
            }                                               
        } else {                                            
            if (S[i] === unEvenFoot) {                      
                result = "No";                              
                break;                                      
            }                                               
        }                                                   
    }                                                       
                                                            
    console.log(result);                                    
}                                                           
                                                             
main(require("fs").readFileSync("/dev/stdin", "utf8"));   