CPS125: Digital Computation and Programming (W2017)

gcc programName.c -o ExecutableName 
clang programName.c -o ExecutableName

Learn how to program using Garden Robot example. Try to solve all the five exercises in order. Caution: the 4th and 5th exercises may require some thinking. Delivered by the Made-With-Code Web project.

Several examples of signed binary/decimal conversion using the two's complement representation are available from this Web page. You can also use this online binary-decimal converter.

1. Read Lab Manual for detailed instructions how to use Quincy-C to write, edit, build and run computer programs.
2. sample0.c (a short introductory program)
3. Experimenting with formatted double placeholder. In the attached C program samplePrintf.c we are consecutively printing same double number using different formats. Try to modify any of these formats using integers of your choice before and after the decimal point. Once you have changed anything in this C program, compile it, build executable, and then execute it. Read Lab Manual if you need help with Quincy C.
4. You can find another simple program illustrating printf and scanf functions here.
5. sample1.c (a longer example illustrating structure of a C program with several functions).

1. readFromFileWithErrors.c A corrected version: readFromFile.c
2. redirection.c programs reads data from this file: data1
3. pointers1.c
4. printingFormats.c
5. pointersPuzzle.c
6. Shortcut operators in C (slides are prepared by Dr. Kosta Derpanis)
7. A C program to demo mixed expressions, explicit casting and shortcut operators in C.

1. Mathematical functions in C, examples: math1.c (sin function)   and   math2.c (random numbers generator).
2. Sample programs illustrating logical expressions in C: logic1.c (error: incorrect comparison)
     and   logic2.c (complex comparison of ASCII character codes )
3. Conditional execution
   • branch1.c (single branch)
   • branch2.c (compound statements and multiple branching)
   • branch3.c (multiple branching using nested if-then conditions)
   • branch4.c (muliple branching usin switch)
   • Find maximum out of 3 numbers using multiple if-else branches.
A branching program with an error: branchError.c   Warning: this program has a number of errors (at least 6). Correct them, compile this program, and then run it.
4. A wrong program with a pointer:   pointerError.c   Correct all errors, and then compile this program.

Project 1 is available. Start working this week! Submit your project before 11pm on Friday February 17.

Several of the following sample programs are taken from King's textbook "C programming: a modern approach", see the link above. Here is the link to additional sample programs on using loops.

Examples of while-loops
• power2.c
• sumNumbers.c In the condition of this while-loop, the number 0 is the sentinel. It determines when the loop has to terminate.
Modify the program above so that it computes an average of all entered numbers.
• squares.c
Modify the program above so that it prints squares of only odd numbers which do not divide 5, i.e., those for which remainder from division by 5 is not 0.
• commission.c
• The fuel tank program Notice that the termination condition in this while-loop depends on the variable supply that can either decrease or increase between iterations.

Examples of for-loops
• maxSquare_for_loop.c  
• oddSquares.c
• Consecutive for-loops: calendar.c
• for-loop that runs forever: cubes.c
• Nested loops: multiplication.c

• Find a quadrant for each point.
• Find the smallest, largest, average, deviation from the entered numbers.
• Print all digits in one column.
• Process daily high temperatures, and find the number of hot, pleasant and cold days. Use data from this file in your program.

On the midterm, there will be no multiple choice questions, only C programs to write. You will be developing your C programs on a computer using Geany. You might wish to install Geany development environment on your Windows computer at home. Then, you can see that its graphical user interface looks similar to Quincy. However, there is no C compiler bundled with Geany. Therefore Geany may not be able to compile and execute C programs on your computer unless you have already installed a C compiler there. In any case, installation of any software at home is your responsibility. The following two links are provided by the CPS125 course coordinator: Geany Portable text editor and basic IDE. Geany Running on Windows.
Note that the following topics discussed at the beginning of this course are NOT included in this midterm, but they will be included in the multiple-choice section on the final exam.

• Convert decimal numbers into signed 32-bit integer (2s complement for negative numbers)
• Convert the 32-bits signed binary numbers into signed decimal numbers
• Convert the signed decimal numbers into signed floating point binary (IEEE-754 32-bits) numbers
• Convert the binary signed 32-bit floating point numbers into signed decimal numbers
• Convert the 8-bit sequences into hexadecimal numbers

• pun.c   (from King's book)
• noReturnValue.c  
• prime.c   (from King's book)
• This is yet another function that has no return value, but nevertheless it is handy thanks to what it does: stars.c  
Examples of functions called by main() function.
• myAverage1.c   In this example, a new function is defined before main(). In the following example, a new function is defined after main(): myAverage2.c   (a similar example is discussed in King's book).
• Recall two different usage of the "star": (1) to declare a pointer variable. For example, int *p;   means p is a variable suitable to keep address in memory where an integer number is located. (2) as the indirection operator which accesses a value stored in memory at an address. For example, *p = (2 + *p); means take a number stored at address pointed by p, add to this number 2, and save it in the memory location pointed by p  .
  The following examples demonstrate how to implement a function that is supposed to return two results. Implement it as a void function working with pointers to arguments. Using these pointers the function can modify both: see swap.c  
• Another example of a function with multiple results: splitSignWholeFraction.c This is a revised version of the example from slides: the function is void, but it computes 3 different results by using 3 pointers to variables as its parameters.

• The following slides about   recursion   are prepared by Dr. Kosta Derpanis.
• This example demonstrates how addition and power functions can be implemented recursively: recursion.c  
• sample1.c   This is a longer example illustrating structure of a C program with several functions; one of them, the factorial function, is recursive.

• C program that initializes an array.  
• C program filling a array from a file.  
• reverseNew.c   Write a C program that prompts the user to enter a series of numbers, then writes the numbers in reverse order. For example:

  	Enter 4 numbers: 5 6 7 8
  	In reverse order: 8 7 6 5
  	

  The following C99 version of this program uses variable length array  
• interest.c   Prints a table of compound interest for a number of years specified by a user assuming that interest rate is also given by an user.
•   Write a program that prompts a long int number from the user, and then checks whether any of the digits in a number appear more than once. After the user enters a number, the program prints either "Repeated digit" or "No repeated digit". For example, the number 349874 has a repeated digit 4; a number like 123456 has no repetitions. The program should use an array digit_seen[digit] where the index digit of this array is an integer from 0 to 9. Initialize every element of this array to 0. When given a number n, the program examines n's digits one at a time, storing each into the digit variable, and then using it as an index into array digit_seen. Depending on the value of this array at index digit, we can determine whether n has repeated digits or not.
  Exercises: (a) Modify this program so that it shows which digits (if any) were repeated in a given number n. (b) Modify this program so that it prints a table showing how many times each digit appears in the number.
• For array a, the expression     sizeof(a) / sizeof(a[0])     can be used to define a macro that represents the size of the array a:

  	#define LENGTH (sizeof(a) / sizeof( a[0]) )
  	

• C program that adds two arrays using a function.  
• maxmin.c   Write a C program that finds the largest and smallest elements in an array. Implement it using a function. The function should take as parameters an array b, its size, and also two pointers max and min to integer variables. Assume that size of the array N is given in advance.
• C program that creates a dynamically allocated 1 dimensional array.  
• dynmaxmin.c   Modify the program finding the largest and smallest elements in an array that is created dynamically.

• An example of a program exampleStructElemSwapWrong.c that is trying (incorrectly) to swapvalues of elements within a structure.   Explain what is wrong in this implementation.
• C program that maintains an inventory: inventory.c   This C program uses this readline.h header file and this readline.c program to read characters into a string.

• This sample program creates a linked list of 4 tree names  
• A function that uses a linked list. The following buggy program is supposed to check whether a tree name occurs in the linked list   Here is a corrected version of this program.
• This program illustrates an expandable linked list with memory dynamically allocated for nodes.   The following expandableTrees.c is a corrected version of this program.
• A simple program that uses command line arguments.  
• A program that accepts two command line arguments in a specific order and sums them up. Adding numbers with command line arguments.  
• planet.c  
• C program that maintains an inventory: linked list version  

• pointersPuzzle.c
• This examples demonstrates how to implement a function that is supposed to return two results as a void function taking two pointers as arguments: swap.c  
• This example demonstrates how addition and power functions can be implemented recursively:   recursion.c  
• The following program reverses an array of numbers (using pointers) reverse3.c  
• C program that reads strings using different functions: readString.c uses scanf, gets fgets with/without replacing \n with \0.