Caesar Cipher 99% done

[pdgaming]

I am working on a caesar cipher encrypter and decrypter program. I got the encrypter part to work. I just need help with the decryption part.

/*
Quick explanation for those who don't know.
In caesar cipher, when encrypting
if key = 1, the sentence XYZ, will be changed to YZA
x+1 = y
y+1 = z
z+1 = a

For decryption, it should, if key = 1
change YZA to XYZ
y-1 = x 
z-1 = y 
a-1 = z

*/

//For encryption, the code was as follows.

  (((int(next)) + key - 65) % 26 + 65)

//int(next) is turning next, which is a char, into an its ascii code.
//key is int to encrypt or decrypt by.
// 65 is ascii code for 1
// 26 letters of the alphabet

I am trying to decrypt with no sucess. This is the last thing left for me to do. Help please!


BTW: the code is supposedly something along these lines: m = (26 + c – k) % 26 and i am supposed to use this as my base code, but I can't figure it out.

//c = (ciphertext)
//m = (plaintext)
//k = (key)

[xxvms]

Can you supply code with your solution?
it makes easier to figure it out then, otherwise we have to come out with whole solution.