Problem 1 - Find the element which has highest occurence in the given array

Problem 1 - Find the element which has highest occurence in the given array

by Neeraj

HTML

<!DOCTYPE html>
<html>

  <head>
    <title>Parcel Sandbox</title>
    <meta charset="UTF-8" />
  </head>

  <body>
    <div id="app"></div>
    <div id="testcase"></div>

    <script src="src/index.js"></script>
  </body>

</html>

CSS

body {
  font-family: sans-serif;
}

.pass {
  color: white;
  background-color: green;
  padding: 10px;
}

.fail {
  color: white;
  background-color: red;
  padding: 10px;
}

JavaScript

document.getElementById("app").innerHTML = `
<h1>Problem 1</h1>
<div>
  Find the element which has highest occurence in the given array
</div>
`;

// Find the element which has highest occurence in the given array

function getMaxOccurrence(arr = []) {
  // Write your code here
  // Write your code here
  // arr = [0, 9, 1, 2, 1, 1, 4, 1, 2, 1, 5];
  var max = 0;
  var maxElement = 0;
  var countArr = {};
  for(var i = 0; i < arr.length; i++) {
  	var count = countArr[arr[i]];
    if(count === undefined) {
    	count = 1;
    } else {
    	count = count + 1;
    }
    countArr[arr[i]] = count;
    if(countArr[arr[i]] > max) {
    	max = countArr[arr[i]];
      maxElement = arr[i];
    }
  }
  
  return maxElement;
  
}

// Example
// getMaxOccurrence([0,9,1,2,1,1,4,1,2,1,5]) => 1

const testCases = [{
    test: [0, 9, 1, 2, 1, 1, 4, 1, 2, 1, 5],
    result: 1
  },
  {
    test: ["e", "a", "b", "c", "b", "a", "c"],
    result: "a"
  },
  {
    test: ["test", "orange", "banana", "banana", "mango", "orange", "orange"],
    result: "orange"
  }
];

const resultString = testCases.map((tc, i) => {
  const {
    test,
    result
  } = tc;
  const actual = getMaxOccurrence(test);
  return `
          <h3> Case ${i + 1}: </h3>
          <p>Expected: ${result}: Actual: ${actual}</p>
          <p>Result: ${
            result === actual
              ? '<span class="pass">PASS<span>'
              : '<span class="fail">FAIL<span>'
          } </p>
      `;
});

document.getElementById("testcase").innerHTML = resultString.join("");