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                <div class="container">
  <div class="row">
    <div class="col-sm-10 mx-auto text-center">
      <div class="card">
          <h2>What City Should You Visit Next</h2>
          <div id="options">
              <h3>Search Options</h3>
              <p>Max Population Size?</p>
              <div class="form-check form-check-inline">
                <input class="form-check-input pop-small" type="radio" name="inlineRadioOptions" id="inlineRadio1" value="Small City">
                <label class="form-check-label" for="inlineRadio1">Small City</label>
              <div class="form-check form-check-inline">
                <input class="form-check-input pop-medium" type="radio" name="inlineRadioOptions" id="inlineRadio2" value="Medium City">
                <label class="form-check-label" for="inlineRadio2">Medium City</label>
              <div class="form-check form-check-inline">
                <input class="form-check-input pop-large" type="radio" name="inlineRadioOptions" id="inlineRadio3" value="Large City">
                <label class="form-check-label" for="inlineRadio3">Large City</label>
        <div id="output">??</div>
        <button class="btn btn-primary btn-lg" onclick="displayMatches()"> Roll The Dice</button>

<div id="createdBy">
  <p>Created By: bNice | 2019</p>


                body {
  padding-top: 4em;
  background: #159957;  /* fallback for old browsers */
background: -webkit-linear-gradient(to right, #155799, #159957);  /* Chrome 10-25, Safari 5.1-6 */
background: linear-gradient(to right, #155799, #159957); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
  font-family: "ZCOOL KuaiLe", cursive;

.hidden {
  display: none;

#output {
  height: 8rem;
  display: flex;
  justify-content: center;
  flex-direction: column;
  text-align: center;
  font-size: 1.8em;
  padding: 2rem;
  background: lightgreen;
  margin-bottom: 1rem;
  color: #333;

.card {
  padding: 4em;
  background: #eee;
  opacity: .8;

#createdBy {
  padding: 2em 0 1rem 3rem;
  color: #fff;



                const smallCities = cities.filter(function(p) {
    return p.population > 36877 && p.population < 150000;
  const medCities = cities.filter(function(p) {
    return p.population > 150001 && p.population < 300000;
  const largeCities = cities.filter(function(p) {
    return p.population > 300001;

// Convert population values in object from type string type to integer.
function convertJson(cities) {
 for (var i = 0; i<cities.length; i++) {
   cities[i].population = parseInt(cities[i].population, 10);

//add commas to numbers / found on github.
function numberWithCommas(x) {
  return x.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ',');

//display matches
function displayMatches() {
  const rnum = Math.floor(Math.random() * cities.length);
  //select output id to print to
    const output = document.querySelector("#output");
  //print to id
    output.innerHTML = cities[rnum].city + ', ' + cities[rnum].state + '<br> Population: ' + numberWithCommas(cities[rnum].population);

const smallRadio = document.querySelector('.pop-small');
const medRadio = document.querySelector('.pop-med');
const largeRadio = document.querySelector('.pop-large');