How is the word “Cleaning” coded in the given language?

Following rules have been applied for obtaining codes of different words-

For the first alphabet in the code:

If number of letters in the word is even, letter succeeding the first letter of the word in the alphabetical series.

If number of letters in the word is odd, letter preceding the last letter of the word in the alphabetical series.

For the number in the code: Difference between alphabetical position numbers of the first and last letters in the word.

For the last alphabet in the code: Letter which precedes the letter appearing at the above obtained number position in the alphabetical series.

For example: METRE

Since it is a 5 letter word, E - 1 = D

13 (M) – 5 (E) = 8

8 - 1 = 7 (G)

So, the code for METRE is D8G.

Thus, the code for “Cleaning” is “D4C”.