Exponentiation Operator

Part of the Fundamentals section of Coddy's PHP journey — lesson 17 of 71.

The exponentiation operator (**) raises a number to a power. It's a cleaner way to write "multiply a number by itself" a certain number of times.

<?php
echo 2 ** 3; // Outputs: 8
?>

Here, 2 ** 3 means 2 raised to the power of 3, which is 2 × 2 × 2 = 8. The first number is the base, and the second is the exponent.

<?php
$base = 5;
$exponent = 2;
$result = $base ** $exponent;
echo $result; // Outputs: 25
?>

You can also use this operator with decimal exponents. For example, raising a number to the power of 0.5 gives you its square root:

<?php
echo 16 ** 0.5; // Outputs: 4
echo 9 ** 0.5;  // Outputs: 3
?>

Challenge

Easy

Read two numbers from input: a base and an exponent.

Calculate and print the result of raising the base to the power of the exponent using the exponentiation operator.

Example:

If the inputs are 3 and 4, the output should be 81 (because 3⁴ = 3 × 3 × 3 × 3 = 81).

Cheat sheet

The exponentiation operator (**) raises a number to a power:

<?php
echo 2 ** 3; // Outputs: 8 (2 × 2 × 2)
?>

The first number is the base, and the second is the exponent.

<?php
$base = 5;
$exponent = 2;
$result = $base ** $exponent;
echo $result; // Outputs: 25
?>

Decimal exponents are also supported. For example, raising a number to the power of 0.5 gives its square root:

<?php
echo 16 ** 0.5; // Outputs: 4
echo 9 ** 0.5;  // Outputs: 3
?>

Try it yourself

<?php
// Read input
$base = intval(fgets(STDIN));
$exponent = intval(fgets(STDIN));

// TODO: Write your code below to calculate base raised to the power of exponent


// Output the result
echo $result;
?>

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

Exponentiation Operator

Cheat sheet

All lessons in Fundamentals