Based on the chapter Data Structure and Pointers, some of the important questions are covered in this question paper. The questions are prepared from the book back and the creative questions.
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Questions:

Generic 2

4 x 2 = 8

Write a function in ALTERSUM (int B[][5], int N, int M) in C++ to find and return the sum of elements from all alternates elements of a two dimensional array starting fromB[0][0].

Write a function in c++, with accept an integer array and its size as parameters and replace the elements having odd values with the thrice its value and the element having even with twice its values.

e.g.If an array contains the elements as 3,4,5,16,9. then the function should rearrange the array as 9,8,15,32,27

Write a Get1From2() function in c++ to transfer the content from two array FIRST[] and SECOND[] to array ALL[].the even places(0,2,4...) of array ALL[] should get the content from the array First[] and odd places (1,3,5,...) of the array ALL[] should get the content from the array SECOND[].
e.g if the FIRST[]array contain
30,60,90
and the SECOND[] array contains
10,50,80
The ALL[] array should contain
30,10,60,50,90,80

What are the drawbacks of linear queue?

Generic 4

5 x 4 = 20

Write a function in C++ to perform push operation in a dynamically allocated stack containing admission numbers of students. Also,declare the relevant class/structure and points.

Given the following class:
char *msg[]={:overflow"."underflow"};
class stack
{
int top;//the stack pointer
int stk[5];//the elements
void err_rep(int e_num)
{
cout< }
//report error message
public:
void init(){top=0;}
//initialise the stack pointer
void push(int);
//put new value in stack
void pop();
//get the pop value
};
Define pop outside the stack.In your definition take care of underflow condition. Function pop should invoke error_rep to report underflow

Write a function in C++ to perform push operation on a dynamically allocated stack containing real numbers.

Write a function in C++ to insert an element in a dynamically allocated queue,where each node contains a Name(char) as data.Assume the following definition of THENODE for the same:
structTHENODE
{
char Name[20];
THENODE *Link;
};

Write a function QINSERT() in C++ to perform insert operation on a linked queue, which contains client no and Client name.Consider the following definition of NODE in the code of QINSERT():
struct NODE
{
long int Cno; //Client number
char Cname[20]; //Client name
NODE *Next;
};

Fill up / 1 Marks

2 x 1 = 2

10.

How wil you know that a linear queue is full?

11.

An array circular queue[10] of integers exixt,where currently
Rear=0, Front=1
Answer the following questions based on the above given data:
(i) How many values arte there in queue?
(ii) If five valuesare deleted,whatwould be the new value of Front?

Generic 3

6 x 3 = 18

12.

Evaluate the following postfix expression using a stack.Show the contains of stack after execution of each operation.
TRUE,FALSE,TRUE,FALSE,NOT,OR,TRUE,OR,OR,AND

13.

Evaluate the following postfix expression showing the status after execution of each step:
10,40,+,8,2,+,*,10,-

14.

Evaluate the following postfix notation of expression:
True,False,NOT,AND,True,True,AND,OR

15.

Why are parentheses needed to specify the order of operations in infix expression but not in postfix expression?

16.

Give the output of the following program segment (assume all required header files are include in the program)
void main()
{
  char *NAME="a ProFile";
  for(int x=0;x<strlen(NAME);x++)
   if(islower(NAME[x]));
else
   if(isupper(NAME[x]))
   if(x%2!=0)
   NAME[x]=tolower(NAME[x-1]);
else
   NAME[x]--;
cout<<NAME<<end1;
}

17.

Obtain the output from the following C++ program as expected to appear on the screen after its exection.
Important note
  All the desired header files are alraedy included in the code, which are required to run the code.
   void main()
{
char *Text="AJANTA";|
int *P.Num[]=[1,5,7,9];
   P=Num;
cout<<*P< Text++;
P++;
   cout<<*P< }

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Answers Key:

Generic 2

4 x 2 = 8

int ALTERSUM (int B[][5], int N,int M)
{
  int s=0,c=1;
for(int i=0;i<N;i++)
{
   if(C%2 !=0)
s = s+B[i][j];
   c++;
  }
  return s;
}

void Rearrange(int A[],int size)
{
   for(int i=0;i<size;i++)
{
   if(A[i]%2 == 0)
   A[i] *= 2;
else
   A[i] *= 3;
   }
}

void Get1FRom2(int FIRST[],int ECOND[],
{
int ALL[6];
for(j=1,i=0;j {
   ALL[i] = FIRST[j];
}
for(j=1,i=0;J   {
   ALL[j] = SECOND[i];
  }
}

Drawbacks of linear queue are:
By the definition of a queue, when we add an element in queue, Rear pointer is increased by 1 whereas, when we remove an element, Front pointer is increased by 1.
But, in array implementation of queue this may cause problem as follows:

Consider the operations performed on a queue(with SIZE=5) as follows:
(i) Initially, empty queue is there so, Front=-1 and Rear=-1
Front=-1
Rear=-1

0 1 2 3 4

(ii)When we add 5 elements in queue, the state of the queue becomes as follows with Front=0 and Rear=4
Front=0
Rear=4

0 1 2 3 4

(iii) Now suppose, we delete 2 elements from queue,then the state of the queue becomes as follows, with Front=2 and Rear=4
Front=2
Rear=4

0 1 2 3 4

(iv) Now, actually we have deleted 2 elements from queue so, there should be space for another 2 elements in the queue, but as Rear pointer is pointing at last position. So, queue overflow condition is reached.
(Rear==SIZE-1) is true, we can't insert new element in the queue even if it has an empty space.To overcome this problem, there is another variation of queue called circular queue.

Generic 4

5 x 4 = 20

struct node
{
int admno;
node *link;
};
node *push(node *top,int va1)
{
node *temp=new node;
temp->admno=va1;
temp->link=NULL;
if(top=NULL)
top=temp;
else
{
temp->link=top;
top=temp;
}
return(top);
}

The function is:
void stack:: pop()
{
if(top==0)
err_rep(1);
else
cout< }

struct Node
{
  float data;
  Node *next;
};
Node *Top=NULL;
void Push(float num)
{
  Node *nptr=new Node;
nptr->data=num;
nptr->next=NULL;
if(Top==NULL)
   Top=nptr;
else
{
   nptr->next=Top;
   Top=nptr;
  }
   cout<<"\nItem Inserted";
}

void insert(THENODE *rear)
{
THENODE *newptr=new THENODE;
newptr->Link=NULL;
cout<<"Enter name for new NODE";
gets(newptr->Name);
if(rear==NULL)
{
front=rear=newptr;
}
else
{
rear->Link=newptr;
rear=newptr;
}
}

void QINSERT()
{
   NODE *N=new NODE;
   cout<<"Enter the client Number and Name";
   cin>>N->Cno>>N->Cname;
N->Next = NULL;
if( FRONT == NULL && REAR == NULL )
FRONT = REAR = N;
else
{
   REAR->Next = N;
   REAR = N;
}
}

Fill up / 1 Marks

2 x 1 = 2

10.

()
In a linear queue,if Rear is equal to maximum size then queue is full.

11.

()
(i) 10
(ii) Front = 6

Generic 3

6 x 3 = 18

12.

In the given, expression true and false are operands and AND, NOT and OR operators.

Scanned Elements	operation	Stack Status
TRUE	PUSH TRUE	TRUE
FALSE	PUSH FALSE	TRUE,FALSE
TRUE	PUSH TRUE	TRUE,FALSE,TRUE
FALSE	PUSH FALSE	TRUE,FALSE,TRUE,FALSE
NOT	POP one operand NOT FALSE=TRUE PUSH TRUE	TRUE,FALSE,tRUE,TRUE
OR	POP two operands Evaluate: TRUE OR TRUE=TRUE PUSH TRUE	TRUE,FALSE,tRUE
TRUE	PUSH TRUE	TRUE,FALSE,TRUE,TRUE
OR	POP two operands Evaluate: TRUE OR TRUE=TRUE PUSH TRUE	TRUE,FALSE,TRUE
OR	POP two operands Evaluate: FALSE OR TRUE=TRUE PUSH TRUE	TRUE,TRUE
AND	POP two operands AND TRUE=TRUE PUSH TRUE	TRUE

Output TRUE

13.

The stack operation is:

Scanned Elements	Operation	Stack Status
10	Push 10	10
40	Push 40	10,40
+	Pop 40,Pop10 Calculate 40+10=50 Push 50	50
8	Push 8	50,8
2	Push 2	50,8,2
+	Pop 2,Pop 8 Calculate 2+8=10 Push 10	50,10
*	Pop 10,Pop 50 Calculate 10*50=500 Push 500	500
10	Push 10	500,10
-	Pop 10,Pop 500 Calculate 500-10=490 Push 490	490

Output 490

14.

Scanned Elements	Stack Status
True	True
False	True,False
NOT	True,True
AND	True
True	True,True
True	True,True,True
AND	True,True
OR	True

Output True

15.

Main advantage of using postifix or prefix expression is that parentheses are not required to enclose the operations. so,the problem of nesting of expression is removed.Every operator in a postfix or prefix expression is placed according to its prexcdence. Therefore, no ambiguity exists in interpreting arithmetic expression.

16.

a Orooile

17.

Output
1AJANTA
5JANTA