[SuperZen]

<script>

  function uniqueArray(count, maxNumber) {
    if (count > maxNumber) return new Error('count > maxNumber')
    const tmp = []
    while (count) {
      const n = parseInt(Math.random() * maxNumber)
      !tmp.includes(n) && (tmp.push(n), count--)
    }
    return tmp
  }

  console.log(uniqueArray(10, 100))
  console.log(uniqueArray(100, 10))

</script>