GRADE (TA use only) __________________


                                                                     (1 point) USER NAME: ___________________________

1. (4 points)
   1. Use the preprocessor directive #define to set the constant PI to 3.14159.

      
      

   2. Use the compile-time directive const to set the constant NUM to the integer 100.

      
      
      

2. (6 points)   Examine the following code segment and indicate the output for each part.

           if(x != 23 && y)  
             x++;
           else if(x < 0 || y == 23)
             y--;
           else x += y;
   
           cout << x << "  " << y << endl; 
   
      

   1. x is -48 and y is 0
      
      
   2. x is 33 and y is 55
      
      
   3. x is 16 and y is 23
      
      

3. (4 points)   Hint: Use truth tables.
   1. Rewrite the following C++ statement to make it more robust (less prone to error).
      

      if(x / y && y != 0)    cout << x / y << endl;

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

            if(x < y && y > x)  cout << "Not good.\n";
            cout << "Carry on.\n";

      
      

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

            if(x < y && y >= x)  cout << "Not good.\n";
            cout << "Carry on.\n";

      
      

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

            if(x < y || y >= x)  cout << "Not good.\n";
            cout << "Carry on.\n";

      
      
      

   
   
   
4. (8 points)   What gets printed from each code segment below?

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

      
      

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

      
      

   3.    x = 4;  y = 8; 
         if (y <= x)
           if (x > 8)
             x++;
           else
             y--;
         cout << x << "  " << y << endl;

      
      

   4.    x = 4;  y = 8; 
         if (y <= x)  {
           if (x > 8)
             x++;
         }
         else
           y--;
         cout << x << "  " << y << endl;

      
      
5. (6 points)   Examine the following code.

      cout << " Please enter an integer  ";
      cin >> x;
      switch(x)  {
        case 60:  x--;  x--;  break;
        case 5:   x = x * x;  
        case 31:  x--;  break;
        case 25:  x = 33;
        case 24:  x += 4;
        default:  x++;
      }
        
      cout << x << endl;
   

   1. What is printed if the input is 60?
      
      
      
   2. What is printed if the input is 5?
      
      
      
   3. What is printed if the input is 24?
      
      

   
   
   
   
   
   

   
   
   
   

6. (8 points)   Examine the code below and answer the questions.

           cin >> x >> y;
   
           if (x > 5)  
             if (y < 3)  
               cout << "Electrical\n";
             else                
               cout << "Engineering\n";
           else  
             if (y > 4)         
               cout << "Computer\n";
             else              
               cout << "Science\n"; 

   In terms of x and y, under what conditions will each word be printed?
   
   
   1. Electrical

      
      

   2. Engineering

      
      

   3. Computer

      
      

   4. Science

      
      

7. (6 points)   What is the output from the program below?

           #include<iostream>
           using namespace std;
   
           void func(int, int);
   
           int main()
           {
             int x, y, z;
   
             x = 30;  y = 34; z = 38;
             func(x, y);
             cout << "In main:  "  << x << " " << y << " " << z << endl;
   
           }
   
           void func(int x, int b)  {
             int z;
           
             x = 75;  b = 77; z = 72;
             cout << "In func:  "  << x << " " << b << " " << z << endl;
           }
          

   
   
   
   
   
   
   
   
   

8. (4 points)
   1. What (not how) does the following function do? That is, what happens to the argument?

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

   2. Write a prototype for function mystery( ).

      
      

9. (10 points)
   1. Write a complete C++ function maximum( ) that returns the maximum of three integers. Your code must have only one exit point to receive full credit.

      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      

   2. Write one C++ statement to call maximum( ) and display:       The maximum is XXX.
      where XXX is the returned value. Don't forget the period.

      
      
      

10. (6 points)   With input   .56   .44   .22   .01 what is printed? Watch the line feeds.

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

11. (8 points)   Study the code below.

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

    1. What gets printed from the code above?
       
       
       
    2. Rewrite the code above as a functionally equivalent while loop.
       
       
       
       
       
       
       
12. (9 points)   Fill in the code described in the three *** comments.

    // file Circle.h 
       const double PI = 3.14159;
       class Circle  {
         public: 
           // *** WRITE A PROTOTYPE FOR MEMBER FUNCTION circumference().
    
    
    
           // compute and return area (PI times radius squared)
           double area();
    
           // declare constructor 
           Circle(double r);
    
         private:
           double radius;    // radius of circle in feet 
       }; 
    
    #include <iostream>
    #include "Circle.h"
    using namespace std; 
      int main()
      {
         // *** CREATE A Circle OBJECT o_shape AND PASS 10.14 TO Circle CONSTRUCTOR
    
    
    
    
         // print area and circumference
         cout << "Area: " << o_shape.area() << endl;
         cout << "Circumference: " << o_shape.circumference() << endl;
      }
    
      // Implement Constructor for Circle
      Circle::Circle(double r)  {
        radius = r;
      }
    
      // *** IMPLEMENT area MEMBER FUNCTION 
      double Circle::area()  {
    
    
    
    
          
      }
    
      double Circle::circumference()  {
        return PI * 2 * radius;
      }
    

    
    

    
    
    
    BONUS:   (2 points, all or nothing, no partial credit)

         for(i = -374; i < 528; i += 10)
             process(i);

    1. How many times does the loop execute?
       
       
       
    2. What is the value of i when the loop terminates?

CS 102 Test 1               October 2, 2007

1. 1. #define PI 3.14159
   2. const int NUM = 100;

2. 1. -48  -1
   2. 34  55
   3. 17  23

3. 1. if(y != 0 && x /y)  cout << x / y << endl;

   2. if(x < y)  cout << "Not good.\n";
      cout << "Carry on.\n";
   -OR- if(y > x)  cout << "Not good.\n";
        cout << "Carry on.\n";

   3. if(x < y)  cout << "Not good.\n";
      cout << "Carry on.\n";

   4. if(y >= x)  cout << "Not good.\n";
      cout << "Carry on.\n";

4. 1. 5  4
   2. 5  5
   3. 4  8
   4. 4  7

5. 1. 58
   2. 24
   3. 29

6. 1. x > 5 and y < 3
   2. x > 5 and y >= 3
   3. x <= 5 and y > 4
   4. x <= 5 and y <= 4

7. In func:  75  77  72
   In main:  30  34  38

8. 1. mystery( ) returns the two rightmost digits of the argument.
   2. int mystery(int);    -OR-    int mystery(int identifier);

9. 1. int maximum(int x, int y, int z)
      {
        int max;    // ultimately, holds max value
      
        max = x;    // assume the largest is x
        if(y > max)  max = y;
        if(z > max)  max = z;
        return max;
      }

   2. cout << "The maximum is " << maximum(x, y, z) << ".\n";

10. 0.56  0.44  0.22  
    3  0.22

11. 1. 24  5

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

12. double circumference();
    Circle o_shape(10.14);
    return PI * radius * radius;

BONUS 1. 91
      2. 536