Decision Coverage and Branch Coverage (Asked in ISTQB)

Q.  How many test cases are necessary to cover all the possible sequences of statements (paths) for the following program fragment? Assume that the two conditions are independent of each other:

if (Condition 1)
then statement 1
else statement 2
fi
if (Condition 2)
then statement 3
fi

A. 2 Test Cases
B. 3 Test Cases
C. 4 Test Cases
D. Not achievable

Answer:-A

Q: Given the following:

Switch PC on
Start "outlook"
IF outlook appears THEN
Send an email
Close outlook

A. 1 test for statement coverage, 1 for branch coverage
B. 1 test for statement coverage, 2 for branch coverage
C. 1 test for statement coverage. 3 for branch coverage
D. 2 tests for statement coverage, 2 for branch coverage
E. 2 tests for statement coverage, 3 for branch coverage

Answer:-B


Q. IF A > B THEN
C = A – B
ELSE
C = A + B
ENDIF
Read D

IF C = D Then
Print "Error"
ENDIF

A. 1 test for statement coverage, 3 for branch coverage
B. 2 tests for statement coverage, 2 for branch coverage
C. 2 tests for statement coverage. 3 for branch coverage
D. 3 tests for statement coverage, 3 for branch coverage
E. 3 tests for statement coverage, 2 for branch coverage

Answer:-B

Q: Consider the following:

Pick up and read the newspaper
Look at what is on television
If there is a program that you are interested in watching then switch the the television on and watch the program
Otherwise
Continue reading the newspaper
If there is a crossword in the newspaper then try and complete the crossword

A. SC = 1 and DC = 1
B. SC = 1 and DC = 2
C. SC = 1 and DC = 3
D. SC = 2 and DC = 2
E. SC = 2 and DC = 3

Answer:-E

Q: Given the following code, which is true about the minimum number of test cases required for full statement and branch coverage:

Read P
Read Q
IF P+Q > 100 THEN
Print "Large"
ENDIF

If P > 50 THEN
Print "P Large"
ENDIF

A. 1 test for statement coverage, 3 for branch coverage
B. 1 test for statement coverage, 2 for branch coverage
C. 1 test for statement coverage, 1 for branch coverage
D. 2 tests for statement coverage, 3 for branch coverage
E. 2 tests for statement coverage, 2 for branch coverage

Answer:-B



Q:Disc = 0
Order-qty = 0
Read Order-qty
If Order-qty >=20 then
Disc = 0.05
If Order-qty >=100 then
Disc =0.1
End if
End if

A. Statement coverage is 4
B. Statement coverage is 1
C. Statement coverage is 3
D. Statement Coverage is 2


Answer:-B



Q. What is the smallest number of test cases required to Provide 100% branch coverage?

If(x>y) x=x+1;
else y=y+1;
while(x>y)
{
y=x*y; x=x+1;
}

A. 1
B. 2
C. 3
D. 4

Answer:-B


Q: If the pseudo code below were a programming language ,how many tests are required to achieve 100% statement coverage?

1. If x=3 then
2. Display_messageX;
3. If y=2 then
4. Display_messageY;
5. Else
6. Display_messageZ;
7. Else
8. Display_messageZ;

A. 1
B. 2
C. 3
D. 4


Answer:-C



Q:Using the same code example as question 17,how many tests are required to achieve 100% branch/decision coverage?

A. 1
B. 2
C. 3
D. 4


Answer:-C

Q: This part of a program is given:

WHILE (condition A) Do B
END WHILE
How many decisions should be tested in this code in order to achieve 100% decision coverage?

A. 2
B. Indefinite
C. 1
D. 4

Answer:-A



Q.: Analyze the following highly simplified procedure:

Ask: "What type of ticket do you require, single or return?"
IF the customer wants ‘return’
Ask: "What rate, Standard or Cheap-day?"
IF the customer replies ‘Cheap-day’
Say: "That will be £11:20"
ELSE
Say: "That will be £19:50"
ENDIF
ELSE
Say: "That will be £9:75"
ENDIF

Now decide the minimum number of tests that are needed to ensure that all the questions have been asked, all combinations have occurred and all replies given.

A. 3
B. 4
C. 5
D. 6
Answer:-A

Q: For the following piece of code, how many test cases are needed to get 100% statement coverage?

Procedure X
Read (Color) // Input color from user
IF (Color == “Red”) THEN
Call Roses(Color)
ELSEIF (Color == “Blue”) THEN
Call Violets(Color)
ELSE
PRINT “User is no Shakespeare”
SaveToDatabase(Color)
End Procedure X

 A. 5
B. 3
C. 1
D. 2

Answer:-B