PHP program to find the length of the last word in string

We are given a string. We are required to write a program in PHP to find the length of the last word in the string using inbuilt functions. We have already discussed approach of solving this problem here. This article discusses the PHP solution to the problem. Examples:

Input : "php exercises" 
Output : 9

Input : "geeks for geeks"
Output : 5

We will mainly use these three inbuilt function in PHP to solve this problem:

• substr() Function: This inbuilt function in PHP is used to extract a part of string.
• strrpos() Function: This inbuilt function in PHP is used to find the last position of string in original or in another string. It returns the integer value corresponding to position of last occurrence of the string, also it treats uppercase and lowercase characters uniquely.
• strlen() Function: This inbuilt function in PHP is used to find the length of a string.

The idea to solve this problem using the above mentioned inbuilt function is to first find the position of last occurring space in the string using the strrpos() function. After getting the position of last occurring space we can easily get the last word in the string using the substr() function and store this in a new string variable. At last, we can use the strlen() function to find the length of the last word in the string. 

<?php
// PHP code to find the length of last word
// in a string

    // function to find length of last word
    function length_last_word($string)
    {   
        // position of last occurring space
        // in the string
        $pos = strrpos($string, ' ');
        
        // if the string has only one word
        if(!$pos)
        {
            $pos = 0;
        }
        else
        {
            $pos = $pos + 1;
        }
        
        // get the last word in the string
        $lastWord = substr($string,$pos);
        
        // return length of last word 
        return strlen($lastWord);
    }
    
    // Driver Code
    print_r(length_last_word('geeksforgeeks')."\n");
    print_r(length_last_word('computer science portal')."\n");
    
?>

Output:

13
6