w3resource

JavaScript: Even, odd numbers and their sum in an array

JavaScript Math: Exercise-94 with Solution

Sum and Count of Even and Odd Numbers

Write a JavaScript program to calculate the sum and count of even and odd numbers in an array.

Test Data:
([1,2,3,4,5,6,7]) -> 3,12, 4,16
([2,3,5,1,2,0,3,4,2,3,4)] -> 6,14, 5,15

Sample Solution:

JavaScript Code:

/**
 * Function to count the number of even and odd numbers and their sums in an array.
 * @param {number[]} nums - The array of numbers to be processed.
 * @returns {number[]} - An array containing the count and sum of even and odd numbers, respectively.
 */
function test(nums) {
  let even = 0, odd = 0;
  nums.forEach(number => {
    if (number % 2 === 0) 
      even++;
    else
      odd++;
  });
  return [
    even,
    nums.reduce((s, v) => (!(v % 2) ? s + v : s), 0),
    odd,
    nums.reduce((s, v) => (v % 2 ? s + v : s), 0)
  ];
}

// Test cases
let nums = [1, 2, 3, 4, 5, 6, 7];
console.log("Original array: " + nums);
let result = test(nums);
console.log("Number of even numbers and their sum: " + result[0] + "," + result[1]);
console.log("Number of odd numbers and their sum: " + result[2] + "," + result[3]);

nums = [2, 3, 5, 1, 2, 0, 3, 4, 2, 3, 4];
console.log("Original array: " + nums);
result = test(nums);
console.log("Number of even numbers and their sum: " + result[0] + "," + result[1]);
console.log("Number of odd numbers and their sum: " + result[2] + "," + result[3]);

Output:

Original array: 1,2,3,4,5,6,7
Number of even numbers and their sum: 3,12
Number of odd numbers and their sum: 4,16
Original array: 2,3,5,1,2,0,3,4,2,3,4
Number of even numbers and their sum: 6,14
Number of odd numbers and their sum: 5,15

Flowchart:

JavaScript: Even, odd numbers and their sum in an array.

Live Demo:

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


Improve this sample solution and post your code through Disqus.

Previous: Check downward trend, array of integers.
Next: Last and middle character from a string.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



Become a Patron!

Follow us on Facebook and Twitter for latest update.

It will be nice if you may share this link in any developer community or anywhere else, from where other developers may find this content. Thanks.

https://www.w3resource.com/javascript-exercises/javascript-math-exercise-94.php