PHP Program to find Largest & Smallest numbers in an Array

This sample program is very helpful for the School / College kids who are willing to become a PHP developer.

And in the interviews these kind of questions asked many times. So it is always good to be prepared.

Here is the code:

<html>
<head>
<title>Find Largest & Smallest numbers in an Array - PHP Programming</title>
</head>
<body>
	
	<h3>PHP Program to find Largest & Smallest numbers in a Array by <a href="tutorialsmade.com">Tutorialsmade.com</a></h3>
	Enter the Numbers separated by Commas <br />
	(eg: 12,23,56)
	<br /><br />
	<form method="post">
		<input type="text" name="numbers"/>
		<button type="submit">Check</button>
	</form>
</body>
</html>

<?php 
	
	if($_POST)
	{
		//get the post value from form
		$numbers = $_POST['numbers'];
		
		//separate the numbers and make into array
		$numArray = explode(',', $numbers);
		
		//assign the first value of the above array for the Largest & Smallest variables
		$largest  = $numArray[0];
		$smallest = $numArray[0];
		
		
		//now loop through each numbers and find which is Largest & Smallest numbers in a PHP Array
		foreach($numArray as $num){
			
			
			if($num > $largest){
				$largest = $num;
			}
			else if($num < $smallest){
				$smallest = $num;
			}
			
		}
				
		//print the output

		echo "Largest Number is: $largest <br />";
		echo "Smallest Number is: $smallest";

	}
	
	

?>

Read the comments in the above source code to understand it.

Once you go through the code, you may get the below concepts:

1. How to capture POST value from a HTML form into PHP.
2. How to separate a string with delimiters, (explode() function) and convert into an Array.
3. How to loop through a PHP Array
4. And obviously how to find the Largest / Smallest number from an Array without using any Build-in PHP function.

Demo is here:

Enjoy Programming!