\n"; echo "Now we will test the decrypt function
\n"; $decrypted = decrypt($encrypted); echo "The decrypted version of {$encrypted} is {$decrypted}"; function encrypt($string) { // replace all A's with B's and all C's with D's $string = str_replace('A', 'B', $string); $string = str_replace('C', 'D', $string); return($string); } function decrypt($string) { // to decrypt all we have to do is replace all B's with A's and all D's with C's $string = str_replace('B', 'A', $string); $string = str_replace('D', 'C', $string); return($string); } ?>