PHP Exercises: Get the head of a given list

Last update on December 20 2024 10:24:22 (UTC/GMT +8 hours)

Write a PHP program to get the head of a given list.

Sample Solution:

PHP Code:

<?php
// Function definition for 'head' that takes an array of items as a parameter
function head($items)
{
    // Use 'reset' to retrieve the first element of the array
    return reset($items);
}

// Call 'head' with an array and display the result using 'print_r'
print_r(head([1, 2, 3]));

// Display a newline
echo "\n";

// Call 'head' with another array and display the result using 'print_r'
print_r(head([2, 1, 3, -4, 5, 1, 2]));

?>

Explanation:

Function Definition:

The function head is defined to take a single parameter, $items, which is expected to be an array.

Retrieve First Element:

Inside the function, reset($items) is used to reset the internal pointer of the array to its first element and return that element.

Example Usage:

The function is called with the array [1, 2, 3]:

The result (first element 1) is displayed using print_r.

A newline is printed for formatting.

Second Example Usage:

The function is called again with another array [2, 1, 3, -4, 5, 1, 2]:

The result (first element 2) is displayed using print_r.

Purpose:

The head function serves to extract and return the first element of any given array, providing a simple way to access the initial value.

Output:

1
2

Flowchart:

PHP Code Editor:

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