'use strict';
const main = input => {
  const s = input[0];
  for (let i = 0; i < s.length; i++) {
    if ((((i+1)%2 == 1) && (s[i] == 'L')) || (((i+1)%2 == 0) && (s[i] == 'R'))) {
      console.log('No');
      return;
    }
  }
  console.log('Yes');
}
main(require("fs").readFileSync("/dev/stdin", "utf8").split('\n'));