How to implement string flip in PHP

This time I will show you how to implement string flipping in PHP. What are the precautions for PHP to implement string flipping? . The following is a practical case, let's take a look.

The example in this article describes how to implement the string flip function in PHP. Share it with everyone for your reference, the details are as follows:

When it comes to the method of achieving string reversal, everyone will think of using

loop. Indeed, looping is a small memory footprint and simple to implement. But there is another way to achieve such a function, and that is recursion.

PHP supports

recursive functions. A recursive function is the function calling itself. These functions are particularly useful for dynamically browsing data structures such as joined lists and trees.

Example:

<?php 
//递归实现字符串翻转
function reverse_r($str){
  if(strlen($str)>0){
    reverse_r(substr($str,1));
  }
  echo substr($str,0,1);
  return;
}
//循环实现字符串翻转
function reverse_i($str){
  for($i=1; $i<=strlen($str);$i++){
    echo substr($str,-$i,1);
  }
  return;
}
reverse_r("Hello");
reverse_i("everyone");
?>

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!

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