Even or Odd Number (JavaScript)

Determining whether a number is even or odd is a fundamental concept in programming that introduces the modulo operator in JavaScript. An even number is an integer that is exactly divisible by 2, leaving no remainder. An odd number is an integer that is not exactly divisible by 2, leaving a remainder of 1.

The core idea is to check the remainder when a number is divided by 2.

The modulo operator (%) returns the remainder of a division.

Explanation:

• inputNumber % 2 calculates the remainder when inputNumber is divided by 2.
• If the remainder is 0, the number is even.
• If the remainder is not 0 (typically 1 or -1 for negative odd numbers in JavaScript), the number is odd.

• Zero (0): By mathematical definition, 0 is an even number because it can be expressed as 2 multiplied by an integer (0 = 2 * 0).
• Negative Numbers: The concept of even and odd applies to negative integers as well. For example, -4 is even, and -7 is odd. The modulo operator in JavaScript correctly handles negative numbers for this purpose.

• Modulo Operator: A crucial operator for remainder calculations, widely used in various programming problems.
• Divisibility: Understanding divisibility rules is key to solving problems related to factors and multiples.
• Conditional Statements: if-else statements are fundamental for making decisions in your code based on conditions.