NAME: _____________________________________           GRADE (TA use only) _____________

1. (6 points)   Examine the following code segment and indicate the output for each part.

           if(x != 20 && y)  
             x++;
           else if(x < 0 || y == 20)
             y--;
           else x += y;
   
           cout << x << "  " << y << endl; 
    

   a. x is -15 and y is 0
   
   b. x is 20 and y is 60
   
   c. x is 30 and y is 50
   
   

2. (6 points)   Hint: Substitute actual values to see what the code does.

   a. Rewrite the following C++ code segment to make it more efficient and to remove any unnecessary code.

         if(x < y  &&  y >= x)  cout << "Okay.\n";
         

   
   b. Rewrite the following C++ code segment to make it more efficient and to remove any unnecessary code.

         if(x < y  &&  y > x)  cout << "Okay.\n";
         

   
   c. Rewrite the following C++ code segment to make it more efficient and to remove any unnecessary code.

         if(x < y  ||  y >= x)  cout << "Okay.\n";
         

   
   

   
   
3. (3 points)   What gets printed from the code segment below?

      x = 5;  y = 5; 
      if (y <= x)  {
        if (x > 8)
          x++;
      }
      else
        y--;
      cout << x << "  " << y << endl;

   
   
4. (6 points)   Examine the following code.

      cout << " Please enter an integer  ";
      cin >> x;
      switch(x)  {
        case 30:  x--;  x--;  x--;  break;
        case 5:   x = x * x;  
        case 27:  x--;  break;
        case 25:  x %= 6;
        case 20:  x += 35;
        default:  x++;
      }
        
      cout << x << endl;
   

   a. What is printed if the input is 30?
   
   
   b. What is printed if the input is 5?
   
   
   c. What is printed if the input is 20?
   
   

   
   

5. (5 points)   With input   33   75   14   96 what is printed? Watch the line feeds.

          for(i = 0; i < 3; i++)  {
               cin >> x;
               cout << x % 5 << "  ";
           }
           cout <<  endl << i << "  " << x << endl;
   
   

   
   

6. (8 points)   What is the output from the program below?

           #include<iostream>
           using namespace std;
   
           void mystery(int&, int);
   
           int main()
           {
             int x, y, z;
   
             x = 22;  y = 44; z = 66;
             mystery(x, y);
             cout << "In main:  "  << x << " " << y << " " << z << endl;
   
           }
   
           void mystery(int& x, int b)  {
             int z;
           
             x = 33;  b = 55; z = 77;
             cout << "In mystery:  "  << x << " " << b << " " << z << endl;
           }
          

   
   

   ---

   
   
   

   ---

   
   
   

7. (4 points)
   a. Complete the sentence to tell what (not how) function mystery ( ) does? That is, what happens to the argument?

         int mystery(int x)  
         {
           return x / 100;
         } 
   
   

           Function mystery( ) returns

   
   
   b. Write a prototype for function mystery( ).

   
   

8. (8 points)   Study the code below.

        for(i = 2, x = 1; i <= 10 && x <= 20; i++)
          x = x * i;
        cout << x << "  " << i << endl;

   a. What gets printed from the code above?
   
   
   b. Rewrite the code above as a functionally equivalent while loop.
   
   
   
   
   
   
   
   

9. (4 points) You have the following declarations:

       char array[NROWS][NCOLS];    // NROWS and NCOLS are global constants
   

   Write a code segment to put a dollar sign in the upper right and lower left corners of array.

   
   
   
   

10. (4 points) You have the following code:

        const int SIZE = 10;
        int array[SIZE] = {0}, index;
        
        for(index = 1; index < SIZE; index += 2)   // start at index 1
          array[index] = 5;

    Fill in the values for the array elements.
    

                  0    1    2    3    4    5   6    7    8    9 
      
    
      

    
    
11. (5 points) Given the following declarations, what value is computed by each of the program statements below? For part e, include the decimal point, and show your answer to two decimal places. Watch integer division!

        int w = 256, x = 43, y = 10, z;
        double c;
    
        a.  z = x/y + y/x;      z:
    
        b.  z = x % y;          z:
    
        c.  z = w % y * y;      z:
       
        d.  z = w % 100 / y;    z:
    
        e.  c = x/y; (Careful!) c:  

    
    

12. (4 points) Write one logical expression to test whether x is in the range -10 through +10, inclusive. Note: all we want is the expression.

    
    
    

13. (4 points)   Carefully study the nested loops. What is displayed?

      a.  i = j = x = y = 0;          // set variables to 0
    
          for(i = 15; i > 10; i--)  {
            x++;
            for(j = 44; j < 44; j++)
              y++;
          }
          cout << i << "  " << j << "  " << x << "  " << y << endl;
    
    
       b.  i = j = x = y = 0;          // set variables to 0
    
           for(i = 10; i < 10; i++)  {
               x++;
               for(j = 0; j > 33; i--)
                   y++;
           }
           cout << i << "  " << j << "  " << x << "  " << y << endl;
    

    
    
    

14. (8 points) Examine the following code segment.

      ifstream infile;
      infile.open ("mydata.dat");
      if (infile.fail())
      {
        cout << "Input file failed to open.\n");
        exit(1);
      }
      
    
      a. What actual file holds the data originally?
    
    
    
      b. Is infile an object or a class?
    
    
      
      c. What effect does exit(1) have on the program?
    
    
    
      d. True or false, the open statement initializes the
         stream variable infile by connecting it to mydata.
    
    
    

BONUS:   In recognition of the outstanding effort of the Tennessee Lady Vols basketball team, this test has 25 free points rather than 20. Congratulations on winning the SEC!!!

1.   a. -15  -1
     b. 80  60
     c. 31  50

2.  a. if(x <= y)  cout << "Okay.\n";  -OR-  if(y >= x)  cout << "Okay.\n";
    b. if(x < y)  cout << "Okay.\n";   -OR-  if(y > x)   cout << "Okay.\n";
    c. if(x <= y)  cout << "Okay.\n";  -OR-  if(y >= x)  cout << "Okay.\n";

3.  5  5

4.  1. 27
    2. 24
    3. 56

5.  3  0  4  
    3  14 

6.  In mystery:  33 55 77
    In main:  33 44 66 

7.  a. Function mystery() truncates the two rightmost digits of a.
    b. int mystery(int);  -OR-  int mystery(int parm_name);

8.  a. 24  5

    b. i = 2;
       x = 1;
       while(i <= 10 && x <= 20)
       {
         x = x * i;
         i++;
       }

9.  array[0][NCOLS-1] = '$';
    array[NROWS-1][0] = '$';

10. 0  5  0  5  0  5  0  5  0  5

11. a. 4
    b. 3
    c. 60
    d. 5
    e. 4.00

12. if(x >= -10 && x <= 10)

13. a. 10  44  5  0
    b. 10  0  0  0

14.	a. mydata.dat
    b. object
    c. The program terminates.
    d. true