PHP Exercises: Create a new string made of every other character starting with the first from a given string

Last update on May 28 2025 09:29:44 (UTC/GMT +8 hours)

29. Every Other Character String

Write a PHP program to create a new string made of every other character starting with the first from a given string.

Sample Solution:

PHP Code :

<?php
// Define a function that extracts characters at even positions in a string
function test($s)
{
    // Initialize an empty string to store the result
    $result = "";

    // Iterate through the string
    for ($i = 0; $i < strlen($s); $i++) {
        // Check if the index is even and append the character to the result
        if ($i % 2 == 0) {
            $result .= substr($s, $i, 1);
        }
    }

    // Return the final result
    return $result;
}

// Test the function with different input strings
echo test("Python")."\n";
echo test("PHP")."\n";
echo test("JS")."\n";
?>

Explanation:

Function Definition:

The test function takes a single parameter, $s, which is a string. The function extracts and returns characters located at even index positions.

Initialize Result Variable:

An empty string $result is initialized to store characters found at even positions.

Iterate Through String:

A for loop iterates through each character of the string $s from index 0 to strlen($s) - 1.

Check for Even Indexes:

Inside the loop, the code checks if the index $i is even using the condition $i % 2 == 0. If true, it appends the character at index $i to $result.

Return Final Result:

After the loop completes, $result contains all characters from even positions in the string, which is then returned.

Output:

Pto
PP
J

Visual Presentation:

PHP Basic Algorithm Exercises: Create a new string made of every other character starting with the first from a given string.

Flowchart:

For more Practice: Solve these Related Problems:

Write a PHP script to generate a new string composed of every second character from the original, starting with the first character.
Write a PHP function to iterate through the characters of a string and selectively concatenate every other character into a new string.
Write a PHP program to create an alternate-character string using a loop and index checking, without using built-in slicing.
Write a PHP script to use array conversion of a string and then reassemble every other element into a resulting string.

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PHP Code Editor:

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