ISTQB CTAL-TTA Exam With Confidence Using Practice Dumps

Program tax check

Integer: tax_rate

real: tax%

BEGIN

tax% := 0

GET (tax_rate)

WHILE tax_rate > 0 loop

IF tax_rate > 3 THEN

tax_rate := 3

ENDIF

tax% := tax% + (tax_rate / 10)

tax_rate := tax_rate - 1

ENDLOOP

IF tax% > 0.6 THEN

print ("tax rate is high")

ELSEIF tax% < 0.1 THEN

print ("tax rate is zero")

ELSE

print ("tax rate is low")

ENDIF

END tax check

Explanation of Control Flow:

Initialization:

tax% := 0

Get Tax Rate:

GET (tax_rate)

While Loop:

Loop runs while tax_rate > 0.

Inside the loop:

If tax_rate > 3, set tax_rate to 3.

Update tax% by adding tax_rate / 10.

Decrement tax_rate by 1.

Post-Loop Condition Checks:

After the loop, check the value of tax%:

If tax% > 0.6, print "tax rate is high".

Else if tax% < 0.1, print "tax rate is zero".

Otherwise, print "tax rate is low".

Unreachable Code Analysis:

The ELSEIF tax% < 0.1 THEN condition (line 17) is unreachable.

In the loop, tax% is incremented by a minimum of 0.1 each time tax_rate is greater than 0.

Therefore, tax% cannot be less than 0.1 after the loop.

Conclusion:

Line 17 (ELSEIF tax% < 0.1 THEN) will never be true given the logic of the loop.

The control flow graph provided illustrates the decision points for an airline's upgrade and boarding process. Decision coverage is a measure of the percentage of decision points executed during testing:

Test 1 covers the decision points: Gold card? (Yes) and Business full? (No).

Test 2 covers: Gold card? (No) and Economy full? (No).

Test 3 covers the decision that leads to being bumped from the flight, which is Economy full? (Yes) and Business full? (Yes).

From the given tests, the decision points for Gold card? (No) and Business full? (No) are not tested, leaving us with 4 out of 6 decision points covered, which is approximately 67% decision coverage.

Cyclomatic complexity is a measure of the number of linearly-independent paths through a program's source code, which is often used as a measure of the complexity of a program. The control flow graph provided represents the logic of a software component and has more than 5 nodes with decision points, indicating that the complexity would exceed the maximum allowed value of 5. The calculation for cyclomatic complexity is V(G) = E - N + 2P, where E is the number of edges, N is the number of nodes, and P is the number of connected components. In this case, the calculated cyclomatic complexity exceeds the allowed threshold, thus a defect should be reported.