***PRACTICE EXAM 01 for***
CS16 Midterm Exam 1
E01, 09S, Phill Conrad, UC Santa Barbara
Actual exam scheduled for: 10/21/2009

Name: ________________________________________________________

Umail Address: __________________________________@ umail.ucsb.edu


Circle Lab section:        8AM             10AM           11AM             noon

Link to Printer Friendly PDF Version

Please write your name only on this page. That allows me to grade your exams without knowing whose exam I am grading.

This exam is closed book, closed notes, closed mouth, cell phone off,
except for:

• You are permitted one sheet of paper (max size 8.5x11") on which to write notes
• These sheets will be collected with the exam, and might not be returned
• Please write your name on your notes sheet

There are 100 points worth of questions on the exam, and you have 50 minutes to complete the exam.

A hint for allocating your time:

• if a question is worth 10 points, spend no more than 5 minutes on it
• if a question is worth 20 points, spend no more than 10 minutes on it
• etc.

1. (20 pts) Write the definition of a C function that takes two numbers (real numbers, not necessarily integers) as parameters, and returns the larger of the two numbers (or if they are equal, the value they are both equal to.)
   
   Write ONLY the function definition—for this question, I do NOT want a complete C program, so do NOT include any extraneous stuff such as #include <stdio.h> or a main function. (See solution)
   
   
   
   
   
   
   
2. (20 pts) There is an incomplete program below. It includes:
   
   
   • the skelton of a main() function (incomplete)
   • a function definition for inToCm()— this function converts from an integer number of inches into centimeters (possibly with a decimal involved).

   Add the code that would be necessary, so that this is a complete interactive program that will convert from inches to centimeters. Include code in main that prompts the user for input (using printf/scanf) and then prints the result of a function call to inToCm() for the user to see the result.
   
   See the extra handout for sample output from this program.
   
   Syntax hints:

   • Be sure to use the proper % specifiers for various types (%d or %i for int, and %lf for double)
   • Remember the special syntax detail that applies to using scanf.
   • Be sure to include the special line of code that brings in "standard input/output" functions
   • Be sure to include a "function prototype" for inToCm, since the main program (that includes the function call) appears before the function definition.
   • Do what is needed at the end of the output so that the Unix prompt after the program ends appears on a new line.
     
     See a sample solution
     

   // inToCmInteractive.c     Answer to a practice exam quesiton
   // P. Conrad, for CS16   10/16/2009
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   int main()
   {
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   }
   
   double inToCm(int inches)
   {
     return inches * 2.54;
   }
   

3. (20 pts) For each of the following C expressions, fill in the value, and then circle the type. The first two are done for you as an example.
   (See solution)
   
   

   expression	value	type
   3	3	int       double        char         char *
   0.5 * 0.5	0.25	int       double        char         char *
   '3'		int       double         char         char *
   "3"		int       double         char         char *
   1 / 10		int       double         char         char *
   5 / 2.0		int       double         char         char *
   26 % 5		int       double         char         char *
   5 % 2		int       double         char         char *
   1.0 / 10		int       double         char         char *
   1 + 3 * 5		int       double         char         char *
   1 + 1 / 2		int       double         char         char *
   2.0 / 4.0 + 1		int       double         char         char *

   
   
   
   
   
   
4. (12 pts) Convert each of the following numbers according to the instructions given:
   (No solution given—you can practice these types of questions here)
   
   
   1. Convert 110 111 010 from base 2 to octal
      
      
      
      
      
   2. Convert 1110 0111 from base 2 to base 10
      
      
      
      
      
   3. Convert 0011 1101 0011 1000 from base 2 to base 16
      
      
      
      
      
   4. Convert 66 from base 10 to base 2
      
      
      
      
      
   5. Convert 157a from hexadecimal to binary
      
      
      
      
      
   6. Convert 644 from octal to binary
      
      
      
5. (8 pts) In test-driven development, we often write a stub before we write the main function. Why?
   
   (no solution given—but if you review what we did in lab02, the answer will reveal itself to you.)
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

End of Exam

Total points: ?

-bash-3.2$ ./inToCmInteractive 
This prorgram converts inches to cm
Please enter inches: 2.54
The answer is: 5.080000 
-bash-3.2$ ./inToCmInteractive 
This prorgram converts inches to cm
Please enter inches: 1
The answer is: 2.540000 
-bash-3.2$ ./inToCmInteractive 
This prorgram converts inches to cm
Please enter inches: 2
The answer is: 5.080000 
-bash-3.2$ ./inToCmInteractive 
This prorgram converts inches to cm
Please enter inches: 36
The answer is: 91.440000 
-bash-3.2$