Question

1. For each of the following, write C++ statements that perform the specified task. Assume that unsigned integers are stored in four bytes and that the starting address of the built-in array is at location 1002500 in memory.

1. Declare an unsigned int built-in array values with five elements initialized to the even integers from 2 to 10. Assume that the constant size has been defined as 5.
2. Declare a pointer vPtr that points to an object of type unsigned int.
3. Use a for statement to display the elements of built-in array values using array subscript notation.
4. Write two separate statements that assign the starting address of built-in array values to pointer variable vPtr.
5. Use a for statement to display the elements of built-in array values using pointer/offset notation.
6. Use a for statement to display the elements of built-in array values using pointer/offset notation with the built-in array’s name as the pointer.
7. Use a for statement to display the elements of built-in array values by subscripting the pointer to the built-in array.
8. Refer to the fifth element of values using array subscript notation, pointer/offset notation with the built-in array name’s as the pointer, pointer subscript notation and pointer/offset notation.
9. What address is referenced by vPtr + 3? What value is stored at that location?
10. Assuming that vPtr points to values[4], what address is referenced by vPtr -= 4? What value is stored at that location?

2. Combine the statements in part 1 into one C++ program. Here is a sample output of your program.

Part C: Printing the using array subscript notation: Elem. Value Addresses 0 2 00AFFC4C 1 4 00AFFC50 2 6 00AFFC54 3 8 00AFFC58 4 10 00AFFC5C Part E: Printing the array using pointer/offset notation: Elem. Value Addresses 0 2 00AFFC4C 1 4 00AFFC50 2 6 00AFFC54 3 8 00AFFC58 4 10 00AFFC5C Part F: Printing the array using pointer/offset notation with the built-in arrays' name as the pointer Elem. Value Addresses 0 2 00AFFC4C 1 4 00AFFC50 2 6 00AFFC54 3 8 00AFFC58 4 10 00AFFC5C Part G: Printing the array by subscripting the pointer to the built-in array Elem. Value Addresses 0 2 00AFFC4C 1 4 00AFFC50 2 6 00AFFC54 3 8 00AFFC58 4 10 00AFFC5C Part H. Printing the fifth element of values using: 1. Array subscript notation: 10 2. Pointer/offest notation with array name as a pointer: 10 3. Pointer subscript notation: 10 4. Pointer/offset notation: 10 Part I. The address of vPtr + 3 : 00AFFC58 The values storedat vPtr + 3 : 8 Part J. The address of vPtr -= 4 : 00AFFC4C The values stored at vPtr -= 4 : 2 Press any key to continue . . .

Answer 1

#include <iostream>

using namespace std;

int main()
{
   // (A)Declare an unsigned int built-in array values with five elements 
   //initialized to the even integers from 2 to 10.
   //Assume that the constant size has been defined as 5.
   unsigned int A[5]={2,4,6,8,10};
  // (B) Declare a pointer vPtr that points to an object of type unsigned int.
  unsigned int *vPtr;
  //(C) Use a for statement to display the elements of built-in array values using array subscript notation.
  cout<<"Elem.\t Value\t Addresses"<<endl;
  for(int i=0;i<5;i++)
  cout<<i<<"\t  "<<A[i]<<"\t"<<&A[i]<<endl;
  //(D) Write two separate statements that assign the starting address 
  //of built-in array values   to pointer variable vPtr.
  vPtr=&A[0];
  vPtr=A;
  //(E)Use a for statement to display the elements of built-in array values using pointer/offset notation.
  cout<<"Elem.\t Value\t Addresses"<<endl;
  for(int i=0;i<5;i++)
  cout<<i<<"\t  "<<*(vPtr+i)<<"\t"<<(vPtr+i)<<endl;
  //(F) Use a for statement to display the elements of built-in array values using pointer/offset 
  //notation with the built-in array’s name as the pointer.
  cout<<"Elem.\t Value\t Addresses"<<endl;
  for(int i=0;i<5;i++)
  cout<<i<<"\t  "<<*(A+i)<<"\t"<<(A+i)<<endl;
  //(G)Use a for statement to display the elements of built-in array values
  //by subscripting the pointer to the built-in array.
  cout<<"Elem.\t Value\t Addresses"<<endl;
  for(int i=0;i<5;i++)
  cout<<i<<"\t  "<<vPtr[i]<<"\t"<<&(vPtr[i])<<endl;
  //(H) Refer to the fifth element of values using array subscript notation, 
  //pointer/offset notation with the built-in array name’s as the pointer, 
  //pointer subscript notation and pointer/offset notation.
  
    cout<<"Printing the fifth element of values using:"<<endl;
    cout<<"1. Array subscript notation:"<<A[4]<<endl;
    cout<<"2. Pointer/offest notation with array name as a pointer:"<<*(A + 4)<<endl;
    cout<<"3. Pointer subscript notation:"<< vPtr[4]<<endl;
    cout<<"4. Pointer/offset notation: "<<*(vPtr + 4)<<endl;
 //(I) What address is referenced by vPtr + 3? What value is stored at that location?
 // (vptr+3) points to memory of 4th element which is 1002512 (if in decimal)
 //100250C (if in hexadecimal).    value stored at that location is 8.
   cout<<"The address of vPtr + 3 :"<<(vPtr + 3) <<endl;
   cout<<"The values storedat vPtr + 3 :"<<*(vPtr + 3) <<endl;
 //(J) Assuming that vPtr points to values[4], what address is referenced by
 //vPtr -= 4? What value is stored at that location?
 //vPtr references Address: 1002500; value stored is 2 ;
 vPtr=&A[4];   //vPtr points to values[4],
 unsigned int *cpy = vPtr;  //cpy points to 0th element
 cout<<"The address of vPtr -= 4 :"<<(vPtr -= 4)<<endl; 
 // vPtr=vPtr-4(move backward 4 elent positions), it points to 0th element.
 vPtr=cpy;   // cpy copied to  vPtr

cout<<"The values stored at vPtr -= 4 :"<<*(vPtr -= 4)<<endl;
//prints the value of 0th element.

cout<<"Press any key to continue . . .";
   
    
    
}

At run time the storage addresses may vary.

Array	A[0]	A[1]	A[2]	A[3]	A[4]
Address(in decimal)	1002500	1002504	1002508	1002512	1002516
Address(hexa)	1002500	1002504	1002508	100250C	1002510
Values	2	4	6	8	10

Since each int is 4 bytes size, next element address=current address +4

vPtr ++ or vPtr=vPtr+1, vPtr advances to address of next element .i.e of vptr= 1002500, then vPtr++ will point to 1002504(address of next element) , not point to 1002501