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During the interview for PHP-related jobs, we are likely to encounter this problem, how to reverse a string. Below we will answer this question for you.
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##Method 1
Grammar strrev(string)
Example
<?php
echo strrev("Hello World!");
?>
Output: !dlroW olleH
Method 2
Split the string into an array, and then traverse and splice it, as followsfunction revstr($str)
{
if (strlen($str) <= 1) return $str;
$newstr = '';
$str2arr = str_split($str,1);
foreach ($str2arr as $word) {
$newstr = $word.$newstr;
}
return $newstr;
}
Method 3## Use recursion, the code is as follows
function revstr($str)
{
if (strlen($str) <= 1) return $str;
$newstr = '';
$newstr .= substr($str,-1).revstr(substr($str,0,strlen($str)-1));
return $newstr;
}ps: This method should be what the interviewer wants to see Answer.
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