'use strict';
function main(input) {
  const arr = input.trim().split('\n');
  const a = arr[0];
  let isStep = true;

  for (let i = 0; i < a.length; i ++) {
    if (a % 2 === 0 && a[i] !== 'L') {
      isStep = false;
    } else if (a % 2 !== 0 && a[i] !== 'R'){
      isStep = false;
    }
  }
  
  console.log(isStep ? 'Yes' : 'No');
}

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