Return the number of characters found in the string "Hello world!" that contains the characters "kHlleo" in PHP

Description

The following code shows how to return the number of characters found in the string "Hello world!" that contains the characters "kHlleo".

Example

  //from  www  .j  a va  2 s.c  o m
<?php
    echo strspn("Hello world!","kHlleo");
    echo strspn("abcdefand","abc");
?>

The code above generates the following result.