JavaScript Program to Find Largest of Two Numbers

Use the JavaScript code const largest = (a, b) => (a > b ? a : b); to find the largest of two numbers by comparing them with the > operator.

Examples

Input5, 10

Output10

Input-3, -7

Output-3

Input8, 8

Output8

How to Think About It

To find the largest of two numbers, compare them using the greater than operator >. If the first number is greater, it is the largest; otherwise, the second number is the largest. If both are equal, either can be returned.

Algorithm

1

Get the two numbers as input.

2

Compare the first number with the second using the > operator.

3

If the first number is greater, select it as the largest.

4

Otherwise, select the second number as the largest.

5

Return the selected largest number.

Code

javascript

function findLargest(a, b) {
  if (a > b) {
    return a;
  } else {
    return b;
  }
}

console.log(findLargest(5, 10));
console.log(findLargest(-3, -7));
console.log(findLargest(8, 8));

Output

10
-3
8

Dry Run

Let's trace the input (5, 10) through the code

1

Compare numbers

Check if 5 > 10, which is false

2

Select largest

Since 5 > 10 is false, select 10 as largest

3

Return result

Return 10

a	b	a > b	largest
5	10	false	10

Why This Works

Step 1: Compare two numbers

The code uses the > operator to check which number is bigger.

Step 2: Choose the larger number

If the first number is greater, it returns that; otherwise, it returns the second.

Step 3: Return the largest

The function returns the largest number as the final result.

Alternative Approaches

Using Math.max()

javascript

function findLargest(a, b) {
  return Math.max(a, b);
}

console.log(findLargest(5, 10));

This is simpler and uses built-in function but may be less clear for beginners.

Using ternary operator

javascript

const findLargest = (a, b) => (a > b ? a : b);
console.log(findLargest(5, 10));

This is concise and modern JavaScript style using arrow functions.

Complexity: O(1) time, O(1) space

Time Complexity

The program compares two numbers once, so it runs in constant time O(1).

Space Complexity

It uses a fixed amount of memory regardless of input size, so space complexity is O(1).

Which Approach is Fastest?

All approaches run in constant time; using Math.max is simplest and most readable.

Approach	Time	Space	Best For
If-else comparison	O(1)	O(1)	Clear logic for beginners
Math.max()	O(1)	O(1)	Concise and built-in function
Ternary operator	O(1)	O(1)	Short and modern syntax