Can you decode these messages?

Here are a few messages in code. After each code, a hint will follow. Type your answers at the comment area. Looking at the alphabet will help you.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Crwwv Mliivtmeq!

Hint: This code can only be decoded if you know the code number. You may discover this number through trial and error, or I can give it to you. It's three. Take each letter, and go up the alphabet three letters.

16,1,21,12 2,21,14,25,1,14

Hint: I think you can figure this one out. Just remember, there are 26 letters in the alphabet.

Now, this one is a combination of the last two:

13,2,26,12,16 25,6,12,12

Hint: I you're on the letter "B", and you have to go back three letters, you go A, Z, Y.

Wcm dr ymtq ceqm?

Hint: This one involves a code word instead of a code number. Look below. Substitute the first part of the alphabet with a code word. Then continue the alphabet, skipping the letters in your code word.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
G L OV E A B C D F H I J K M N P Q R S T U W X Y Z

Lastly, you can make your own code, substituting letters with different ones. And don't forget to answer the question in the code above. Leave your answer in the comment area.

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