Question

Please help with my C++ homework!

1.

The following function is supposed to perform binary search. It has no errors and will execute correctly.

int binarySearch(int array[], int size, int value)
{
   int first = 0,             // First array element
       last = size - 1,       // Last array element
       middle,                // Mid point of search
       position = -1;         // Position of search value
   bool found = false;        // Flag

   middle = (first + last) / 2;     

   while (!found && first <= last)
   {
    

if (array[middle] == value)      
      {
         found = true;
         position = middle;
      }
      else if (array[middle] > value)  
         last = middle - 1;
      else
         first = middle + 1;           
   }
   return position;
}

True/False

13.

If you attempt to open a non-existing file for output

a.It is automatically created if it’s a text file.

b.It is automatically created for both text and binary file.

c.It is automatically created if it’s a binary file.

4.It is automatically created bt only if the file is a text fileThe open fails.

19. If fobj is a object of type fstream, then the following statement

fobj.seekp(32L, ios::beg);

a.sets the write position to the 32rd byte (byte 31) from the beginning of the file

b.You cannot tell from the information given

c.It works differently with different operating systems

d.sets the write position to the 33rd byte (byte 32) from the beginning of the file

20.

If fobj is an object of type fstream, then the following statement

fobj.seekp(120L, ios::curr)

a.sets the write pos to the 121st byte (byte 120) from the current position

b.You cannot tell from the information given

c.It works differently with different operating systems

d.sets the write pos to the 119st byte (byte 118) from the current position

21.

Consider the following code:

int main()

{

      fstream fout ("data.dat", ios::out|ios::binary);

    char c = 'A';

    while (c < 'K')

    {

            fout.write(&c, sizeof(c));

            c++;

    }

    fout.close();

    return 0;

}

After this program is executed, the file “data.dat” will contain the following:

a.Abcdefghij

b.AAAAAAAAAA

c. Cccccccccc

d.ABCDEFGHIJ

22.

Consider the code bellow. The file “letters.dat” contains ABCDEFGHIJ

int main()

{

      fstream fin("letters.dat", ios::in|ios::binary);

      char a;

      fin.get(a);

    cout << a;

      fin.seekg(3, ios::beg);

      fin.get(a);

      cout << a ;

      fin.seekg(-4, ios::end);

     fin.get(a);

     cout << a;

     seekg(2, ios::cur);

     fin.get(a);

     cout << a << endl;

     return 0;

    }

What will be the output?

a.ACEJ

b.Aaaa

c.DEFG

d.ABCD

e.ADGJ

Answer 1

12.
False

13.
b.It is automatically created for both text and binary file.

19.
a.sets the write position to the 32rd byte (byte 31) from the beginning of the file

20.
a.sets the write pos to the 121st byte (byte 120) from the current position

21.
d.ABCDEFGHIJ

22.
e.ADGJ