$ logErr $=$ true;

$display $=$ "display:none;";

$//$TASK c $-$ replace "aaaa" with the proper superglobal variable to capture all the post array elements

if $($aaaa $==$ "POST"$)\{$

$display $=$ "display:block;";

$//$TASK d $-$ replace $"$bbbb$"$ with the proper superglobal variable to capture the username field

$usr $=$ validate$\_$fields $($bbbb$)$;

if $($empty$($$usr$))\{$

$usrErr $=$ "Username is required";

$$logErr=$ true;

$\}$ elseif $(!$preg$\_$match$($$pattern,$usr$))\{$

$usrerr $=$ "Only letters allowed";

$$logErr=$ true;

$\}$ else $\{$

$\}$

$//$Task e $-$ replace $"$cccc$"$ with the proper superglobal variable to capture the password field

$$psw=$ validate$\_$fields$($cccc$)$;

$//$TASK $f-$ using the pattern above, create a new pattern to validate the password field

$pattern $="$;

if $($empty$($$psw$))\{$

$pswErr $=$ "Password is required";

$$logErr=$ true;

$\}$ elseif $(!$preg$\_$match$($$pattern,$psw$))\{$

$pswerr $=$ "Invalid Password";

$$logEr=$true;

$\}$ else $\{$

$$logErr=$ false;

$\}$

$\}.$

if $($ $ logerr