The aptitude test consisted tricky questions on core subjects of CSE like C , C++, Java ,Data Structures along with answer keys.

1. Technical
Aptitude Test
Date : 18-03-2016

2. Q.1. Choose one that apply:
class S{
public static void main(String agr[]){
short s1=4; //LINE 1
short s2 = s1+=s1; //LINE 2
short s3= s1+s2; //LINE 3
byte b1=(byte)s1 +(byte)s2; //LINE 4
byte b2=(byte)((byte)s1 +(byte)(byte)s2); //LINE 5 }}
A. Comiler Error at Line 1,2,3 B. Compiler Error at Line 3,4.
C. Compiler Error at 2,3,5 D. Comiler Error at 1,4,5

3. Q.2 Classes that can be used to instantiate objects are called concrete
classes.
A.TRUE B.FALSE
Q. 3. char ** array [12][12][12]; Consider array, defined above. Which
one of the following definitions and initializations of p is valid?
A) char ** (* p) [12][12] = array;
B) char ***** p = array;
C) char * (* p) [12][12][12] = array;
D) const char ** p [12][12][12] = array;
E) char (** p) [12][12] = array;

4. Q.4 What is the result of following java code?
public class Apti {
static void test(int[] a) {
int[] b = new int[2];
a = b;
System.out.print(b.length);
System.out.print(a.length); }
public static void main(String[] args) {
int[] a = new int[5];
test(a);
System.out.print(a.length);
}
}
A.225 B.255 C.200 D.222

5. Q.5 what is the o/p?
main(){
printf(“%%%%%”);
}
A.%%%%%
B.%%%%
C.%%%
D.%%

6. Q.6 . #include<iostream>
using namespace std;
int x = 1;
void fun(){
int x = 2;
{
int x = 3; cout << ::x << endl;
}
}
int main()
{
fun();
return 0;
}
A.1 B.2 C.3 D.0

7. Q.7 What will be the result of compiling and running the following
program ?
public class ExceptionTest{
public static void main(String[] args) throws Exception{
try{
m2();
}finally{ m3(); }
catch ( NewException e ){}
}
public static void m2() throws NewException { throw new
NewException(); }
public static void m3() throws AnotherException{ throw new
AnotherException(); }
A. It will compile but will throw AnotherException when run.
B. It will compile but will throw NewException when run.
C. It will compile and run without throwing any exceptions.
D. It will not compile.

8. Q. 8 main(){
extern int i;
i=20;
printf("%d",i); }
Output is:
(A)0
(B)20
(C)would vary from compiler to compiler
(D)Error : Undefined symbol i
Q.9 Which type of casting can be used only with pointers and
references to objects?
A) Dynamic_cast B) cast C)Static_cast D) Pointer_Cast

9. Q.10 class Student extends String{} What happens when we try to compile
this class?
A) Will not compile because class body is not defined
B) Will not compile because the class in not declared public.
C) Will not compile because String is abstract.
D) Will not compile because String is final.
Q. 11 What will be output when you will execute following c code?
#include<stdio.h>
void main(){
int a=5,b=10;
if(a<++a||b<++b)
printf("C rocks, everyone shocks");
else
printf("%d %d",a,b);
}
(A)6 11 (B)6 10 (C)C rocks, everyone shocks (D)none of above

10. Q.12 What will the following code print?
int[] scores1 = { 1, 2, 3, 4, 5, 6};
int[] scores2 = { 0, 0, 0, 0, 0, 0};
System.arraycopy(scores2, 2, scores1, 3, 2);
for(int i : scores2) System.out.print(i);
A. 123006
B. 000000
C. 000450
D. It throw an exception at run time.

11. Q.13. int main() {
int number1 = 88, number2 = 22;
int & refNumber1 = number1;
refNumber1 = 11;
cout << refNumber1 << endl;
refNumber1 = number2;
number2++;
cout << refNumber1 << endl;
cout << number1 << endl;
cout << number2 << endl;
} O/p:-
A.88 23 23 23 B.11 22 22 23 C.11 22 23 23
D.11 23 23 23 E.88 22 22 23

12. Q.14 What will be output when you will execute following c code?
#include<stdio.h>
void main(){
int a=5; a=a>=4;
switch(2){
case 0:int a=8;
case 1:int a=10;
case 2:++a;
case 3:printf("%d",a);
}
}
(A) 2 (B) 10 (C) Compilation error (D)no output

13. Q.15 Which of the following should be used 'if content is not fixed and
keep on changing(mutable) but Thread safety is required'?
A. String B. StringBuffer C. StringBuilder D. Both B & C
Q.16 #include<stdio.h>
void main(){
int a=3,b=2;
a=a = = b = = 0;
switch(a){
case 1:a=a+10;
}
sizeof(a++);
printf("%d",a);
}
(A)11 (B)12 (C)1 (D)0
Associativity : left to right

14. Q.17 Which of the following concepts means waiting until runtime to
determine which function to call?
A. Data hiding B. Dynamic casting C. Dynamic binding D.
Dynamic loading
Q.18 Which of the following are true about the "default" constructor?
Choose 2 options:
A. It is provided by the compiler only if the class does not define any
constructor.
B. It initializes the instance members of the class.
C. It calls the default 'no-args' constructor of the super class.
D. It initializes instance as well as class fields of the class.
E. It is provided by the compiler if the class does not define a 'no- args'
constructor.

15. Q.19 What will be output when you will execute following c code?
#define PRINT printf("Star Wars");printf(" Psycho");
#include<stdio.h>
void main(){
int x=1;
if(x--)
PRINT
else
printf("The Shawshank Redemption");
} Choose all that apply:
(A) Stars Wars Psycho
(B) The Shawshank Redemption
(C) Warning: Condition is always true
(D) Compilation error

16. Q.20 Why reference is not same as a pointer?
A. A reference can never be null.
B. A reference once established cannot be changed.
C. Reference doesn't need an explicit dereferencing mechanism.
D. All of the above.
Q.21 Which of the following sorting algorithms can be used to sort a
random linked list with minimum time complexity?
A.Insertion Sort B.Quick Sort C.Heap Sort D.Merge Sort
Explanation: Both Merge sort and Insertion sort can be used for linked lists.
The slow random-access performance of a linked list makes other
algorithms (such as quicksort) perform poorly, and others (such as
heapsort) completely impossible. Since worst case time complexity of
Merge Sort is O(nLogn) and Insertion sort is O(n^2), merge sort is
preferred.

17. Q.22. A circularly linked list is used to represent a Queue. A single
variable p is used to access the Queue. To which node should p point
such that both the operations enQueue and deQueue can be performed
in constant time?
A. rear node
B. Front node
C. not possible with single pointer
D. node next to front

18. Q.23 A function f defined on stacks of integers satisfies the following
properties. f(∅) = 0 and f (push (S, i)) = max (f(S), 0) + i for all stacks S
and integers i.
If a stack S contains the integers 2, -3, 2, -1, 2 in order from bottom to
top, what is f(S)?
A.6 B.4 C.3 D.2
Q.24. In a complete k-ary tree, every internal node has exactly k
children or no child. The number of leaves in such a tree with n internal
nodes is:
A.nk B.(n-1)k+1 C. n(k-1)+1 D.n(k-1)
Q.25. How many distinct binary search trees can be created out of 4
distinct keys?
A.4 B.14 C.24 D.42
The base case is t(0) = 1 and
t(1) = 1

19. Q.26. What is time complexity of fun()?
int fun(int n)
{
int count = 0;
for (int i = n; i > 0; i /= 2)
for (int j = 0; j < i; j++)
count += 1;
return count;
}
A O(n^2) B.O(nLogn) C.O(n) D. O(nLognLogn)

20. Q.27. class Test
{
int p = 20;
public static void main(String args[]){
final Test t = new Test();
t.p = 30;
System.out.println(t.p);
}
}
A.20 B.30 C. Compile time error D. Runtime error

21. Q.28. What will be the result of attempting to compile and run the
following program?
public class TestClass{
public static void main(String args[ ] ){
String s = "hello";
StringBuilder sb = new StringBuilder( "hello" );
sb.reverse();
s.reverse();
if( s == sb.toString() ) System.out.println( "Equal" );
else System.out.println( "Not Equal" );
}
}
A. Compilation error. B. It will print 'Equal'.
C. It will print 'Not Equal'. D. Runtime error.
No reverese method in String.

22. Q.29. Which of the following statements are true?
A. For any non-null reference o1, the expression (o1 instanceof o1) will
always yield true.
B. For any non-null reference o1, the expression (o1 instanceof
Object) will always yield true.
C. For any non-null reference o1, the expression (o1 instanceof o1) will
always yield false.
D. For any non-null reference o1, the expression (o1 instanceof Object)
may yield false.

23. Q.30 import java.util.*;
public class Test {
public static void main(String[] args) {
TreeSet s = new TreeSet();
s.add(1);
s.add(99.9);
s.add(99.9);
s.add(96.9);
for (int i = 0; i < s.size(); i++) {
System.out.print(s.pollFirst()+" ");
} }}
A. 1 96.9 99.9 B.1 96.9 99.9 99.9 C.1 D.compilation error
E.an exception is thrown at run time