Lesson 8

Question 1

FORTRAN I control statements are based on

Answer 1

IBM 704 hardware

Question 2

RESULT OF THE CONTROL STATEMENTS IN THE FORTRAN I EVOLUTION:

Answer 2

All algorithms represented by the flowcharts can be coded with only two way selection statements and pretest loops.

Question 3

CONTROL STRUCTURE

Answer 3

It is a statement and the statments that it controls.

Question 4

What is the issue with the design of the control structure?

Answer 4

Can a control structure have multiple entries?

Question 5

Two general categories of the selection statements

Answer 5

Two way selection

Multiple selection

Question 6

What are the design issue with the two way selection statements?

Answer 6

What is the form and type of the control expression?

How are the then and the else clause specified?

How should the meaning of the nested selectors be specified?

Question 7

When is the control expression placed in the parenthesis?

Answer 7

When the then reserved word or any other syntactic marker is not used.

Question 8

Languages that have the control expression as arithmetic

Answer 8

C89, C99, C++, Python

Question 9

Perl has clauses delimited by braces. T/F

Answer 9

T

Question 10

The clause form in the ruby and the python is

Answer 10

Statement Sequences

Question 11

Semantic rule for the Java nested if

Answer 11

the else clause resonant or matches with the nearest if.

Question 12

AN laternative format to the semantic rule for the Java nested if is used, in which the compund statements are used. Which languages accept this solution?

Answer 12

Java, C, C sharp, C++

Question 13

Which programming language does not allow else-less if statements?

Answer 13

ML

Question 14

In ML, F sharp, Lisp, the selector is an expression. What is the rule for the type of value returned by then and else clause?

Answer 14

They should be of the same type.

Question 15

What are the design issues with the multiple selection statements?

Answer 15

form and type of the control expression

selectable segments specified

is the execution flow through the structure restricted to include just a single slectable segment

cases values specified

What is done about the unrepresented expression values

Question 16

The programming languages that allow the multiple selection statement:

Answer 16

C, C++, Java, and JavaScript

Question 17

What are the design choices for C’s switch statement?

Answer 17

Control and constant expressions are of discreet type (int, char, enum); selectable segments can be statement sequences, bloacks or compound statements; Any number of segments can be executed in the execution of the construct; Default is for the unrepresented values; No restriction on the case expr.

Question 18

What are the design choices for the C sharp’ s multiple selection statements?

Answer 18

Has static semantics ( disallows the implicit execution of more than one segment)
each selecatble segment ends with break or goto
the control expr and the case constants can be strings

Question 19

Ruby’s multiple selections statement form:

Answer 19

case
when boolean expr then expr
……
when boolean expr then expr
[else expr]
end

Question 20

Implementing the multiple selectors

Answer 20

Multiple conditional branching
Store case values in the table and use linear search
A hash table is for more than ten cases
array indices and array values are used for the case values and the case labels if the number of cases is small

Question 21

Scheme’s multiple selector form:

Answer 21

(COND
(predicate expr)
….
[(ELSE expr)]
)

Here, the predicate expr is a param

Question 22

Semantics of the multiple selectors of the Scheme:

Answer 22

The evaluated value of COND is the value of the expr associated with the first predicate expr that is true.

Question 23

What are the design issues with the iteration?

Answer 23

How is the iteration controlled?
Where is the control mechanism in the loop?

Question 24

Counter-controlled loop

Answer 24

A counting iterative statement
has a loop variable
means of specifying the initial, terminal, and the stepsize values

Question 25

Design issues with the Counter-controlled loop:

Answer 25

type and scope of the local variable legal for the loop variable or loop param to be changed loop params should be evaluated only once value for the loop variable after the loop termination.

Question 26

C's design choice for the counter-controlled loops:

Answer 26

If the second expr is absent in the for loop in C, the infinite loop is formed. no explicit loop variable first expr is evaluated only once and rest of the two are evaluated with each iteration legal to branch into the body of a for loop in C

Question 27

C++'s counter controlled loop:

Answer 27

control expression can be boolean initial expr can include the variable definitions

Question 28

Two programming languages that require the control expression to be boolean.

Answer 28

Java and C sharp

Question 29

Python's counter-controlled loop:

Answer 29

The object is a call to the range or the list of the values The else clause is optional and executes if the loop terminates normally.

Question 30

F sharp counter controlled loops:

Answer 30

No counter variables as it is pure functional language, therefore, simulated with the recursive functions.

Question 31

Logically-Controlled loops

Answer 31

based on the boolean expr Desgin issues: postest or pretest? special case of the counting loop or a separate statement?

Question 32

C abd C++ have both posttest and the pretest forms, legal to branch into the loop body, not in Java as it has no goto. (True/False)

Answer 32

True

Question 33

Design issue for the nested loop?

Answer 33

should conditional be part of the exit should control be transferrable out of more than one loop

Question 34

C, c++, Python, Riby and C sharp has the unconditional unlabeled exits. (T/F)

Answer 34

T

Question 35

Which lang have the unconditional labeled exits and labeled versions of continue?

Answer 35

Java and Perl

Question 36

C' s for loop can be used to develop the user-defined iterator. (T/F)

Answer 36

T

Question 37

Java 5.0 for each is an interation based on the data structures. (T/F)

Answer 37

T

Question 38

Ruby blocks

Answer 38

sequences of the code delimited either by the braces or do and end.

Question 39

predefine diterator methods in the Ruby

Answer 39

times, each, upto

Question 40

Python's yield statement:

Answer 40

Any method containing the yield statment is the generator because data is generated one element at the time. history sensitive- same start at the initial as at the termination

Question 41

Unconditional branching

Answer 41

transfers control to the specific place in the program main concern: readability

Question 42

Languages thta does not support the goto statement:

Answer 42

Java, Python, Ruby

Question 43

Which language does not use braces tof orm the compound statement?

Answer 43

Python

Question 44

WHich of the followinf languages does not use static semantic to specify the if construct to which the else clause belongs when the clause follows a nested if?

Answer 44

Ada

Question 45

WHich of the following languages has switch statement that has different static semantic than others?

Answer 45

C sharp

Question 46

WHich of the following languages does not have a counter controlled loop statement tht uses the for special word?

Answer 46

F sharp

Question 47

Which of the following languages have a predefined loop statement that is controlled by the data structure?

Answer 47

Perl, C++, C sharp, Java

Question 48

WHich of the following language has a goto statement?

Answer 48

C sharp, C, Ada