JavaScript: Check whether a number is even or not

JavaScript Function: Exercise-7 with Solution

Check Even or Odd

Write a JavaScript program to check whether a number is even or not.

Visual Presentation:

Sample Solution:

Using recursion:

JavaScript Code:

// Recursive JavaScript function to check if a number is even.
function is_even_recursion(number) {
 // If the number is negative, convert it to its absolute value.
 if (number < 0) { number = Math.abs(number); } // Base case: If the number is 0, it's even. if (number === 0) { return true; } // Base case: If the number is 1, it's odd. if (number === 1) { return false; } else { // Recursive case: Subtract 2 from the number and recursively check the new number. number = number - 2; return is_even_recursion(number); } } // Example usage: Check if certain numbers are even. console.log(is_even_recursion(234)); // true console.log(is_even_recursion(-45)); // false console.log(is_even_recursion(65)); // false 

Output:

true
false
false

Flowchart:

Live Demo:

See the Pen javascript-recursion-function-exercise-7 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that checks if a number is even using recursion without the modulo operator.
• Write a JavaScript function that determines whether a number is even or odd using bitwise operations.
• Write a JavaScript function that recursively checks evenness by subtracting two in each call.
• Write a JavaScript function that combines recursion with iteration to determine if a number is even or odd.

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