function update_user_info($userid=NULL,$email=NULL,$username=NULL)
{
    $update_array = array();
    $i = 0;
    $j = 0;
    
    if( $userid != NULL )
    {
        $update_array['userid'] = $userid[0];
        if("where"==$userid[1])
        {
            $update_array['where'][$i++] = 'userid';
        }
        else
        {
            $update_array['set'][$j++] = 'userid';
        }
        
    }
    
    if( $email != NULL )
    {
        $update_array['email'] = "'".$email[0]."'";
        if("where"==$email[1])
        {
            $update_array['where'][$i++] = 'email';
        }
        else
        {
            $update_array['set'][$j++] = 'email';
        }
        
    }
    
    if( $username != NULL )
    {
        $update_array['username'] = "'".$username[0]."'";
        if("where"==$username[1])
        {
            $update_array['where'][$i++] = 'username';
        }
        else
        {
            $update_array['set'][$j++] = 'username';
        }
        
    }
    
    $set = "";
    $where = "";
    
    if(isset($update_array['set'][0]))
    {
        foreach($update_array['set'] as $value)
        {
            $set .= "`" . $value . "` = " .$update_array[$value] . ", ";
        }
    }

    if(isset($update_array['where'][0]))
    {
        foreach($update_array['where'] as $value)
        {
            $where .= "`" . $value . "` = " .$update_array[$value] . " AND ";
        }
    }
    $set = substr($set,0,-2);
    $where = substr($where,0,-5);
    
    if($userid[0] == $userinfo['userid'] || isset($userinfo['admin_priv']))
    {
        $query = "UPDATE users SET " . $set . " WHERE " . $where;
        $result = mysql_query($query);
        $affected = mysql_affected_rows();
    }
    else return "Incorrect privileges";
}

$userid = array(5,'where');
$username = array('username','set');
update_user_info($userid,NULL,$username);

$email = array('test@example.com','set');
$username = array('username','where');
update_user_info(NULL,$email,$username);

function updateUsername(int UserID, string NewUsername)
{
    Set Username = NewUsername WHERE UserID = UserID
}

function getUserIDFromEmail(string Email)
{
    FROM Users WHERE Email = Email
    return Users.ID
}

updateUsername(getUserIDFromEmail("tom@2+2.com"), "NewUsername")

---- count_words.feature ----
Feature: Count Words

As a user I want to be able to count the words in a given sentence.

Scenario Outline: Count words in a given sentence
  Given the input to count_words is "<input>"
  When count_words is run
  Then the output of word_count should be "<output>"
  
Examples:
  |input|output|
  |A man, a plan, a canal -- Panama|{'a' => 3, 'man' => 1, 'canal' => 1, 'panama' => 1, 'plan' => 1}|
  |Doo bee doo bee doo|{'doo' => 3, 'bee' => 2}|
  |a A a|{'a' => 3}|

---- palindrome.feature ----
Feature: Detect Palindromes

As a user I want to be able to check if a given word or phrase is a palindrome.

Scenario Outline: Provide input to palindrome?
  Given the input to palindrome? is "<input>"
  When palindrome? is run
  Then the output of palindrome? should be "<output>"
  
Examples:
  |input|output|
  |A man, a plan, a canal -- Panama|true|
  |Madam, I'm Adam!|true|
  |Abracadabra|false|

---- count_words_steps.rb ---- 
require_relative 'hw1.rb'

Given /^the input to count_words is "([^"]*)"$/ do |input|
  @input = input
end

When /^count_words is run$/ do
  @output = count_words(@input)
end

Then /^the output of word_count should be "([^"]*)"$/ do |expected_output|
  raise("Wrong Output") unless @output == eval(expected_output)
end

---- palindrome_steps.rb ---- 
require_relative 'hw1.rb'

Given /^the input to palindrome\? is "([^"]*)"$/ do |input|
  @input = input
end

When /^palindrome\? is run$/ do
  @output = palindrome?(@input).to_s
end

Then /^the output of palindrome\? should be "([^"]*)"$/ do |expected_output|
  raise('Wrong Output') unless @output == expected_output
end