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09 - Interpret Correct or Complete Algorithms #1

 1. An algorithm is a process or a set of instructions used to solve a problem

  True

  False

 2. Key algorithm constructs are:

  Sequence

  Iteration

  All of the above

  Selection

 3. In the following algorithm, if more than 35 hours are worked ….
INPUT hours_worked
INPUT pay_rate
IF hours_worked <= 35 THEN
gross_pay = pay_rate x hours_worked
ELSE
gross_pay = (pay_rate x 35)+
(1.5 x pay_rate x
(hours_worked - 35))
ENDIF
OUTPUT gross_pay
END

  the gross_pay is paid for the extra hours

  time-and-a-half is paid for the extra hours

  1.5 + 35 is added to the extra hours rate

  then 35 is added to the extra hours

 4. What does the following algorithm do?
INPUT item_price
INPUT vat_rate
vat_amount = item_price x vat_rate
final_price = item_price + vat_amount
OUTPUT final_price
END

  calculate the Sales Tax (VAT) of an item and then works out the final price of an item

  calculates the final vat amount of any given item with a price of x

  calculates the final price of several items based on their vat rate x the vat amount

  None of the above

 5. How many variables can you count in the following algorithm, and what does it do?
INPUT total_items
SET total_cost = 0
SET count = 0
WHILE count < total_items
INPUT item_price
total_cost = total_cost + item_price
count = count + 1
ENDWHILE
average_price = total_cost / total_items
OUTPUT average_price
END

  five variables - this program calculates the total cost divided by the average price, which gives the final price

  None of the above

  two variables - this program calculates the average price for a number of items

  five variables - this program calculates the average price for a number of items

 6. ______is a detailed yet readable description of what a computer program must do, expressed in a natural language(e.g. english) rather than in a programming language.

  Assembly language

  English Code (EC)

  Pseudocode

  Algorithmic Thinking

 7. All of the following are examples of ________
str(3)
int("3")
float("3.14")

  Masting

  Coling

  Pseudolanguage

  Casting

 8. What is the output of the following algorithm/code -assuming it is in Python?
for i = 0 to 9
print("Hi")

  Outputs "Hi" on the screen 8 times

  None of the above

  Outputs "Hi" on the screen 90 times

  Outputs "Hi" on the screen 9 times

 9. In the following program, if the user enters the password: "open123", what happens?
password = ""
while password != "CdRtp45@"
password = input("Password?")
endwhile

  Error

  The input is accepted and the 'end while' comes into play

  "CdRtp45@" must be entered else, the program repeats

  A prompt asking the user to enter: "CdRtp45@ is displayed

 10. What sort of structure/selection is shown in this algorithm?
switch coinResult:
case "heads":
print("You got heads")
case "tails":
print("You got tails")
default:
print("Not valid coin")
endswitch

  For loops

  IF statements

  While loops

  switch statement (switch/case) - python does not have this and a dictionary could be used to achieve the same thing

 11. What is happening in the following algorithm? Specifically, what happens to the variable x?
a = 0
b = 0
procedure move(x: byVal, y: byRef)
x = x + 1
y = y + 1
endprocedure
move(a, b)
print(a)
print(b)

  the variable x will be passed into y and changing x will change the original value

  the variable x will be passed to the procedure by copying the value. Changing x in the procedure won’t change the original value

  The final value of x = a

  the variable x will be passed to the procedure directly. Changing x changes the original value

 12. What is the output here? Careful - it is not entirely obvious!
some_global = 10
def func1():
 some_global = 20
def func2():
 print(some_global)
func1()
func2()

  30

  20

  40

  10

 13. The programmer wants a variable inside a function to be treated as 'global' and the following code achieves this.
def func1():
 global some_global #use global keyword
 my_global = 20

  TRUE

  FALSE

 14. The following statement will evaluate to ……
(10 >= 1) and (1 < 2)

  FALSE

  TRUE

 15. The following statement will evaluate to …..
>>> (1>2) and (9>=1)

  FALSE

  TRUE

 16. In the following algorithm, the elif has _____ conditional tests.
limbs = 4
if limbs == 4:
 print('no one shall pass')
elif limbs > 0 <4:
 print('tis but a scratch')
else:

  1

  3

  4

  2

 17. What is the output of the following code?
n = 0
for num in range(5):
 n = n + num
print (n)

  10

  20

  15

  5

 18. Which of the following statements is correct, in reference to the following code?
while answer!=”computer”
 answer=input(“What is the
password?”)
endwhile
do
 answer=input(“What is the
password?”)
until answer == “computer”

  The while loop will keep looping while its condition is True.

  The while loop will end if the answer is = "open123"

  The while loop will stop if the condition is True

  None of the above

 19. Which of the following statements is true of this algorithm?
while 1 == 1:
 print ("lol")

  It prints "lol" exactly once

  It does not print "lol" at all, because the while loop condition is never met

  It prints "lol" twice and then crashes, as 1 is already equal to 1

  It creates an infinite loop because 1 is always equal to 1

 20. The following algorithm makes use of a condition controlled loop
	01 input b 
02 for x = 1 to 100 
03     print b * x
04 next

  TRUE

  FALSE