Even numbers are those numbers that are exactly divisible by 2.
The remainder operator % gives the remainder when used with a number. For example,
const number = 6;
const result = number % 2; // 0
Hence, when % is used with 2, the number is even if the remainder is zero. Otherwise, the number is odd.
Example 1: Using if...else
// program to check if the number is even or odd
// take input from the user
const number = prompt("Enter a number: ");
//check if the number is even
if(number % 2 == 0) {
console.log("The number is even.");
}
// if the number is odd
else {
console.log("The number is odd.");
}
Output
Enter a number: 27 The number is odd.
In the above program, number % 2 == 0 checks whether the number is even. If the remainder is 0, the number is even.
In this case, 27 % 2 equals to 1. Hence, the number is odd.
The above program can also be written using a ternary operator.
Example 2: Using Ternary Operator
// program to check if the number is even or odd
// take input from the user
const number = prompt("Enter a number: ");
// ternary operator
const result = (number % 2 == 0) ? "even" : "odd";
// display the result
console.log(`The number is ${result}.`);
Output
Enter a number: 5 The number is odd.
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