PHP program to demonstrate the regular expression to count the occurrence of given substring

Program/Source Code:

The source code to demonstrate the regular expression to count the occurrence of a given substring is given below. The given program is compiled and executed successfully.

<?php
//PHP program to demonstrate the regular expression 
//to count the occurrence of given substring.

$str = "India is a country located in asia";
$pattern = "/in/i";

$count = preg_match_all($pattern, $str);

printf("Total occurrences of are: %d", $count);
?>

Output:

Total occurrences of are: 2

Explanation:

In the above program, we created a string variable $str, which is initialized with "India is a country located in Asia". After that, we used 'i' in the pattern to search case insensitive substring in the specified string. Here we used the preg_match_all() function that will return the total number of occurrences of a specified substring within the string that will be assigned to the variable $count and printed on the webpage using printf() function.