Lists

Learning Objective:

For list operations:

a. Write expressions that use list indexing and list

procedures. 

b. Evaluate expressions that the list indexing and list procedures

The exam reference sheet provides basic

operations on lists, including:

• accessing an element by index

Text:

aList[i]

Block:

aList i

accesses the element of aList at index i.

The first element of aList is at index 1 and

is accessed using the notation aList[1].

• assigning a value of an element of a list to a

variable

Text:

x aList [i]

Learning Objective:

For algorithms involving elements of a list:

a. Write iteration statements to traverse a list

b. Determine the result of an algorithm that includes traversals

Traversing a list can be a complete traversal, where all elements in the list are accessed, or a partial traversal, where only a portion of elements are accessed.

Iteration statements can be used to traverse

a list.

AAP-2.O.3

The exam reference sheet provides

Text:

FOR EACH item IN aList

{

<block of statements>

The variable item is assigned the value of

each element of aList sequentially, in

order, from the first element to the last element.

The code in block of statements is

executed once for each assignment of item.

AAP-2.O.4

Knowledge of existing algorithms that

use iteration can help in constructing new

algorithms. Some examples of existing

algorithms that are often used with lists include:

§ determining a minimum or maximum value in

a list

• computing a sum or average of a list of

numbers

AAP-2.O.5

Linear search or sequential search algorithms

check each element of a list, in order, until the

desired value is found or all elements in the list

have been checked.