const main = input => {
  const S = input.trim()

  let ok = true
  for (let i = 0; i < S.length; i++) {
    if (i % 2 === 0) {
      if (!['R', 'U', 'D'].includes(S.charAt(i))) {
        ok = false
        break
      }
    } else {
      if (!['L', 'U', 'D'].includes(S.charAt(i))) {
        ok = false
        break
      }
    }
  }

  ok ? console.log('Yes') : console.log('No')
}

// 標準入力
main(require("fs").readFileSync("/dev/stdin", "utf8"))
