PHP Exercises: Concat two given strings

Last update on May 30 2022 11:40:59 (UTC/GMT +8 hours)

PHP Basic Algorithm: Exercise-77 with Solution

Write a PHP program to concat two given strings (lowercase). If there are any double character in new string then omit one character.

Sample Solution:

PHP Code :

<?php
function test($s1, $s2)
{
       if (strlen($s1) < 1)
            {
                return $s2;
            }
            if (strlen($s2) < 1)
            {
                return s1;
            }
            return substr($s1, strlen($s1)-1, 1) <> substr($s2, 0, 1) ? $s1 . $s2 : $s1 . substr($s2, 1, strlen($s1)-1);
    }
echo test("abc", "cat")."\n";
echo test("Python", "PHP")."\n";
echo test("php", "php")."\n";

Sample Output:

abcat
PythonPHP
phphp

Flowchart:

PHP Code Editor:

Contribute your code and comments through Disqus.

Previous: Write a PHP program to create a new string taking the first character from a given string and the last character from another given string. If the length of any given string is 0, use '#' as its missing character.
Next: Write a PHP program to create a new string from a given string after swapping last two characters.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.

PHP: Tips of the Day

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

Example:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

Ref : https://bit.ly/3i77vCC