JavaScript: Find the number of even digits in a given integer

JavaScript Basic: Exercise-130 with Solution

Count Even Digits in Integer

Write a JavaScript program to find the number of even digits in a given integer.

Visual Presentation:

Sample Solution:

JavaScript Code:

// Function to count the number of even digits in a given number
function even_digits(num) {
  var ctr = 0;
  // Loop until 'num' becomes 0
  while (num) {
    // Increment 'ctr' if the last digit of 'num' is even
    ctr += num % 2 === 0;
    // Remove the last digit by integer division
    num = Math.floor(num / 10);
  }
  return ctr; // Return the count of even digits
}

// Test cases
console.log(even_digits(123)); // Output: 1
console.log(even_digits(1020)); // Output: 3
console.log(even_digits(102)); // Output: 2 

Output:

1
3
2

Live Demo:

See the Pen javascript-basic-exercise-130 by w3resource (@w3resource) on CodePen.

Flowchart:

ES6 Version:

// Function to count the number of even digits in a given number
const even_digits = (num) => {
  let ctr = 0;

  // Loop until 'num' becomes 0
  while (num) {
    // Increment 'ctr' if the last digit of 'num' is even
    ctr += num % 2 === 0;

    // Remove the last digit by integer division
    num = Math.floor(num / 10);
  }

  return ctr; // Return the count of even digits
};

// Test cases
console.log(even_digits(123)); // Output: 1
console.log(even_digits(1020)); // Output: 3
console.log(even_digits(102)); // Output: 2

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