NIELIT 2017 July Scientist B (IT) - Section B: 26

Question

The following program is to be tested for statement coverage: 

begin 
if(a==b){S1;exit;} 
else if (c==d){S2;} 
else{S3;exit;} 
S4; 
end 

The test cases $T1,T2,T3$ and $T4$ given below are expressed in terms of the properties satisfied by the values of variables $a,b,c$ and $d$. The exact values are not given.

$T1:a,b,c$ and $d$ are all equal 
$T1:a,b,c$ and $d$ are all distinct 
$T3:a=b$ and $c!=d$ 
$T4:a!=b$ and $c=d$ 

Which of the test suites given below ensures coverage of statements $S1,S2,S3$ and $S4$?

• A. $T_1,T_2,T_3$
• B. $T_2,T_4$
• C. $T_3,T_4$
• D. $T_1,T_2,T_4$

Answer 1

Option D 

T1 cover statement S1

because all are equal means a==b true so  only S1 execute and then exit program

 

T2 cover statement S3 

because all are distinct means statement a==b false then c==d false so only  statement S3 execute and then exit program

 

T4 cover statement S2,S4 

given a!=b so statement a==b false means note execute 

given c=d means statement c==d true so S2 execute and here program not exit so  S4 will  be execute also