submit multiple inputs within a forloop in codeigniter

Thank You RobertSF,
can i know where to insert
 // array_search returns the key associated with the value you search
$question_id = array_search('Save', $_POST);

// take away the starting S
$question_id = substr($question_id, 1);

as i did it in controllers i got error.

syntax error, unexpected '$question_id' (T_VARIABLE), expecting function (T_FUNCTION) or const (T_CONST)

PHP Code:

<input type="submit" name="<?php echo 'S' . $row->id; ?>" value="Save" /> 


PHP Code:

// array_search returns the key associated with the value you search
$question_id = array_search('Save', $_POST);

// take away the starting S
$question_id = substr($question_id, 1);