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JavaScript: Find the number which appears most in a given array of integers

JavaScript Basic: Exercise-94 with Solution

Write a JavaScript program to find the number which appears most in a given array of integers.

Pictorial Presentation:

JavaScript: Find the number which appears most in a given array of integers.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Find the number which appears most in a given array of integers</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function array_element_mode(arr) {
  var ctr = [],
    ans = 0;

  for(var i = 0; i < 10; i++) {
    ctr.push(0);
  }
  for(var i = 0; i < arr.length; i++) {
    ctr[arr[i] - 1]++;
    if(ctr[arr[i] - 1] > ctr[ans]) {
      ans = arr[i] - 1;
    }
  }
  return ans + 1;  
}
console.log(array_element_mode([1, 2, 3, 2, 2, 8, 1, 9]))

Sample Output:

2

Flowchart:

Flowchart: JavaScript - Find the number which appears most in a given array of integers

ES6 Version:

function array_element_mode(arr) {
  const ctr = [];
  let ans = 0;

  for(var i = 0; i < 10; i++) {
    ctr.push(0);
  }
  for(var i = 0; i < arr.length; i++) {
    ctr[arr[i] - 1]++;
    if(ctr[arr[i] - 1] > ctr[ans]) {
      ans = arr[i] - 1;
    }
  }
  return ans + 1;
}
console.log(array_element_mode([1, 2, 3, 2, 2, 8, 1, 9]))

Live Demo:

See the Pen javascript-basic-exercise-94 by w3resource (@w3resource) on CodePen.


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Previous: Write a JavaScript program to find the maximum difference among all possible pairs of a given array of integers.
Next: Write a JavaScript program to replace all the numbers with a specified number of a given array of integers.

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JavaScript: Tips of the Day

Classes/function constructors

class Person {
  constructor() {
    this.name = 'Owen';
  }
}

Person = class AnotherPerson {
  constructor() {
    this.name = 'Eddie';
  }
};

const member = new Person();
console.log(member.name);

We can set classes equal to other classes/function constructors. In this case, we set Person equal to AnotherPerson. The name on this constructor is Eddie, so the name property on the new Person instance member is "Eddie".

Ref: https://bit.ly/3jFRBje