... program: 24 , the number of rows on the screen; 80, the number of columns; and 26 , the number of letters in the alphabet. But none of these appears in the code, which makes the num - bers that ... (Prentice Hall, 1994). 20 STYLE CHAPTER 1 The code includes, among others, the numbers 20 , 21 , 22 ,23 , and 27 . They're clearly related or are they? In fact, there are only three numbers ... A singly - linked list is a set of items, each with data and a pointer to the next item. The head of the list is a pointer to the first item and the end of the list is marked by a null pointer....