A logical problem

Question

Friends there is logical problem: I have an array of bytes having values 11,12,5,15,57,75,12,12,12,18,2,26 I want to write the two chunk it in a separate file. The chunk i.e. 11,12,5,15,57,75 and 18,2,26, the continues value of 12 if in three qunatities should be ignored. But it should accopnay in not in three qunatity just like in ist saved chunk. Thanks