PHP Program to Check Power of 3

Posted in PHP Tutorial

Updated on Jan 11, 2024

By Mari Selvan

👁️ 27 - Views

⏳ 4 mins

💬 1 Comment

Photo Credit to CodeToFun

🙋 Introduction

In the realm of programming, one often encounters the need to check if a given number is a power of another.

In this case, we'll explore a PHP program specifically designed to check if a number is a power of 3.

The logic behind this program involves repeatedly dividing the number by 3 until it becomes 1, indicating that it is a power of 3.

📄 Example

Let's delve into the PHP code that achieves this functionality.

isPowerOf3.php

Copied

<?php
// Function to check if a number is a power of 3
function isPowerOf3($n)
{
  // Keep dividing the number by 3 until it is greater than 1
  while ($n % 3 == 0 && $n > 1)
  {
    $n /= 3;
  }

  // If the final value is 1, the original number is a power of 3
  return $n == 1;
}

// Driver program
// Replace this value with your desired number
$number = 27;

// Check if the number is a power of 3
if (isPowerOf3($number))
{
  echo "$number is a power of 3\n";
}
else
{
  echo "$number is not a power of 3\n";
}

?>

💻 Testing the Program

To test the program with different numbers, simply replace the value of $number in the code.

Output

27 is a power of 3

Run the script to see if the given number is a power of 3.

🧠 How the Program Works

The program defines a function isPowerOf3 that takes an integer as input and checks if it is a power of 3.
Inside the function, it repeatedly divides the number by 3 until it becomes greater than 1.
If the final value is 1, the original number is a power of 3, and the function returns true; otherwise, it returns false.
The driver program tests a specific number and prints whether it is a power of 3 or not.

📏 Between the Given Range

Let's take a look at the php code that checks for powers of 3 in the given range.

isPowerOfThree.php

Copied

<?php
// Function to check if a number is a power of 3
function isPowerOfThree($number)
{
  while ($number > 1)
  {
    if ($number % 3 !== 0)
    {
      return false;
    }
    $number /= 3;
  }
  return $number === 1;
}

// Check power of 3 in the range 1 to 20
echo "Power of 3 in the range 1 to 20:\n";
for ($i = 1;$i <= 20;$i++)
{
  if (isPowerOfThree($i))
  {
    echo "$i ";
  }
}

?>

💻 Testing the Program

Output

Power of 3 in the range 1 to 20:
1 3 9

Run the script to see the numbers that are powers of 3 in the range from 1 to 20.

🧠 How the Program Works

The program defines a function isPowerOfThree that checks if a given number is a power of 3.
Inside the function, it uses a while loop to repeatedly divide the number by 3 until it is no longer divisible by 3.
The main section then iterates through numbers in the range 1 to 20, calling the function to check if each number is a power of 3.
Numbers that are powers of 3 are printed.

🧐 Understanding the Concept of Power of 3

Before diving into the code, let's understand the concept of a power of 3.

A number is considered a power of 3 if it can be expressed as 3^n, where n is an integer.

For example, 1, 3, 9, 27, and so on are powers of 3.

🎢 Optimizing the Program

While the provided program is straightforward, there are alternative approaches to check if a number is a power of 3. Consider exploring other mathematical techniques for optimization.

Feel free to incorporate and modify this code as needed for your specific use case. Happy coding!