###### Multiplicative Cipher

In a Multiplicative cipher, each character of the alphabet is assigned a value (starting at a zero index [A=0, B=1, etc]) and a coprime key to the length of the alphabet is chosen. Each character is multiplied with this key and the corresponding letter is substituted.
Example the letter M (12th letter in this zero indexed alphabet) and key 3 would be 12 * 3 = 36. 36 modulo 26 = 10 so the letter K would be chosen. Note: This cipher is closely related to the Affine cipher.
var plain = "plaintext";
var customid = "";
var customidnum = 0;
var customaz09 = 0;
var customid1 = "";
var customidnum1 = 0;
var customaz09_1 = 0;
var ignorechar = 0;
var encrypttext = "ciphertext";

###### Plaintext:

**Key =**