function main(arg) {
	arg = arg.trim();
  	var s = arg.length;
  	var out = 'Yes';
 	for (var i = 0; i < s; i++) {
    	var num = arg[i];
      	var index = i + 1;
      	if (index%2 === 0 && num === 'R') {
              	return console.log('No');
        } else if (index%2 === 1 && num === 'L'){
        		return console.log('No');
        }
    }
  	console.log(out)
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'));