- explode: documentation ( source)
- array_pop: documentation ( source)
<?php
$str = "asd asd
cxv fgg
fds fda
";
$strArray = explode(PHP_EOL, $str);
$last = array();
foreach ($strArray as $s) {
$tmp = explode(' ', $s);
$last[] = array_pop($tmp);
echo $last[0];
}