Substitution Cipher by Using Attributes of Magic Number 9

This method works on the principle of substitution cipher but by using attributes of magic number 9. Total there are 5 strings created and used for encryption and decryption. Randomly symbols are substituted (after performing arithmetic operations) from 5 different strings. Furthermore these 5 strings changes from file to file. For decryption these 5 strings must be available. This method is simple to understand and implement but difficult, robust and compact to decrypt.