Determine if a string is collapsible: Difference between revisions

=={{header|PHP}}==

<lang PHP><?php

function collapseString($string) {

$previousChar = null;

$collapse = '';

$charArray = preg_split('//u', $string, -1, PREG_SPLIT_NO_EMPTY);

for ($i = 0 ; $i < count($charArray) ; $i++) {

$currentChar = $charArray[$i];

if ($previousChar !== $currentChar) {

$collapse .= $charArray[$i];

}

$previousChar = $currentChar;

}

return $collapse;

}

function isCollapsible($string) {

return ($string !== collapseString($string));

}

$strings = array(

'',

'another non colapsing string',

'"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ',

'..1111111111111111111111111111111111111111111111111111111111111117777888',

"I never give 'em hell, I just tell the truth, and they think it's hell. ",

' --- Harry S Truman ',

'0112223333444445555556666666777777778888888889999999999',

"The better the 4-wheel drive, the further you'll be from help when ya get stuck!",

'headmistressship',

"😍😀🙌💃😍😍😍🙌",

);

foreach ($strings as $original) {

echo 'Original : <<<', $original, '>>> (len=', mb_strlen($original), ')', PHP_EOL;

if (isCollapsible($original)) {

$collapse = collapseString($original);

echo 'Collapse : <<<', $collapse, '>>> (len=', mb_strlen($collapse), ')', PHP_EOL, PHP_EOL;

} else {

echo 'Collapse : string is not collapsing...', PHP_EOL, PHP_EOL;

}

}</lang>

{{out}}

<pre>Original : <<<>>> (len=0)

Collapse : string is not collapsing...

Original : <<<another non colapsing string>>> (len=28)

Collapse : string is not collapsing...

Original : <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> (len=72)

Collapse : <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> (len=70)

Original : <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> (len=72)

Collapse : <<<.178>>> (len=4)

Original : <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> (len=72)

Collapse : <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> (len=69)

Original : <<< --- Harry S Truman >>> (len=72)

Collapse : <<< - Hary S Truman >>> (len=17)

Original : <<<0112223333444445555556666666777777778888888889999999999>>> (len=55)

Collapse : <<<0123456789>>> (len=10)

Original : <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> (len=80)

Collapse : <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> (len=77)

Original : <<<headmistressship>>> (len=16)

Collapse : <<<headmistreship>>> (len=14)

Original : <<<😍😀🙌💃😍😍😍🙌>>> (len=8)

Collapse : <<<😍😀🙌💃😍🙌>>> (len=6)</pre>