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  <h1> dice randomness distribution</h1>
    This page throws the dice from <a href=""></a> a given number of times and shows
    how the result matches the expected distribution of randomness.
    <input name="iterations" value="10000000" />
    <button>Roll Dice!</button>

    <caption>Comparison of expected and actual distribution of <span class="iterations"></span> dice throws</caption>

        <td value="0">6.25%</td>
        <td data-value="0"></td>
        <td value="1">25.00%</td>
        <td data-value="1"></td>
        <td value="2">37.50%</td>
        <td data-value="2"></td>
        <td value="3">25.00%</td>
        <td data-value="3"></td>
        <td value="4">6.25%</td>
        <td data-value="4"></td>


                @import url("");

a {
  color: inherit;

article {
  display: block;
  flex-shrink: 0;
  box-sizing: border-box;
  width: 90%;
  max-width: 90%;
  padding: 0.5em 1.5em;
  margin: 1em auto;
  font-size: 1.4em;
  background-color: #202930;
  box-shadow: 0 0 0.6em 0.3em black;
  color: white;

body {
  background: #202930
    url("") repeat;
  background-size: 35vmin;
  font-family: Nunito, sans-serif;
  font-size: 1em;
  line-height: 1.6em;

input {
  border-radius: 0.15em;
  padding: 0.15em 0.3em;
  margin: 0.3em;
  font-family: Nunito, sans-serif;
  font-size: 2em;
  color: white;
  cursor: pointer;
  background-color: rgba(0, 0, 0, 0.8);
  transition: background-color 0.1s ease-in-out;

button {
  border: 3px solid white;

button:hover {
  background-color: #151a1f;
  transition: background-color 0.1s ease-in-out;

caption {
  padding: 0.3em;
  caption-side: bottom;
  font-size: 50%;

form {
  text-align: center;

h1 {
  margin-top: 0.2em;
  margin-bottom: 0.15em;
  font-size: 1.5em;

input {
  text-align: right;
  max-width: 6.5em;

table {
  table-layout: auto;
  width: 50%;
  border-collapse: collapse;
  margin: auto;

td:last-child {
  font-weight: bold;

td {
  border: 1px solid white;
  padding: 0.5em;
  text-align: center;

tr:nth-child(odd) td {
  background-color: #151a1f;

.minus {
  color: red;
.plus {
  color: green;
.zero {
  color: lime;
.running {
  opacity: 0.35;



                function calculateScores(iterations) {
  window.CP.PenTimer.MAX_TIME_IN_LOOP_WO_EXIT = 10000;

  const scores = {
    0: 0,
    1: 0,
    2: 0,
    3: 0,
    4: 0

  for (let counter = 0; counter < iterations; counter++) {
    const diceValue = countDiceUp(generateRandomDiceValues());

  return scores;

document.querySelector("form").addEventListener("submit", (event) => {

  const resultTable = document.querySelector("table");
  const iterations = parseInt(

  document.querySelector(".iterations").innerText = iterations.toLocaleString();

  const scores = calculateScores(iterations);

  const expected = {
    0: 6.25,
    1: 25.0,
    2: 37.5,
    3: 25.0,
    4: 6.25

  for (const [dieNumber, count] of Object.entries(scores)) {
    const percentage = ((100 / iterations) * count).toFixed(2);
    const deviation = (expected[dieNumber] - percentage).toFixed(2);

    const element = document.querySelector(`[data-value="${dieNumber}"]`);
    const deviationElement = element.nextElementSibling;

    let className;
    if (deviation < 0) {
      className = "minus";
    } else if (deviation > 0) {
      className = "plus";
    } else {
      className = "zero";

    element.innerText = `${percentage}%`;
    deviationElement.innerText = `${deviation}%`;
    deviationElement.className = className;