CSC 351 - Chapter 8

Question 0

selection statement

Answer 0

provides a way of choosing between two or more execution paths

Question 1

control structure

Answer 1

a control statement and the collection of statements whose execution it controls

Question 2

multiple-selection statement

Answer 2

allows the selection of one of any number of statements ( switch statement)

Question 3

iterative statement

Answer 3

causes a statement to be executed zero, one or more times. often called a loop

Question 4

loop variable

Answer 4

where the count value is maintained

Question 5

how do functional languages control repetition?

Answer 5

instead of iteration, they use recursion

Question 6

what is a block?

Answer 6

is a sequence of code that can be used with specially written methods to create useful constructs

Question 7

selection statement design issues

Answer 7

• what is the form and type of the expression that controls the selection?
• how are the then and else clauses specified?
• how should the meaning of nested selectors be specified?

Question 8

iterative counter-controlled statement design issues

Answer 8

• what are the type and scope of the loop variable?
• should it be legal for the loop variable/parameters to be changed in the loop?
• should the parameters be evaluated only once, or once for every iterations?

Question 9

solution for nesting two-way selectors

Answer 9

use a static semantics rule rather than a syntatic entity

Question 10

iterative statement design issues

Answer 10

• how is iteration controlled?

- where should the control mechanism appear in the loop

Question 11

multiple selection statement design issues

Answer 11

• what is the form and type of the expression that controls the selection?
• how are the selectable segments specified?
• is execution flow through the structure restricted?
• how are the case values specified?
• how should unrepresented selector expression values be handled?

Question 12

pretest loop

Answer 12

the test for loop completion occurs before the loop body is executed

Question 13

posttest loop

Answer 13

the test for loop completion occurs after the loop body is executed

Question 14

logically controlled loops design issues

Answer 14

• should the control be pretest or posttest?

- should the logically controlled loop be a special form of a counting loop or a separate statement?

Question 15

purpose of user located loop control statements

Answer 15

allow programmers to choose a location for loop control other than the top or bottom of the body (break, goto)

Question 16

user located loop control mechanism design issues

Answer 16

• should the conditional mechanism be an integral part of the exit?
• should only one loop body be exited?

Question 17

unconditional branch statement

Answer 17

transfers execution control to a specified location in the program