Differences

This shows you the differences between two versions of the page.

--- haas:fall2014:data:projects:node1 [2014/09/21 21:31] – [Your task] wedge
+++ haas:fall2014:data:projects:node1 [2014/09/21 22:02] (current) – [node library] wedge
@@ Line 204: / Line 204: @@
 None of these files denote an entire runnable program. These are merely standalone functions. The various programs under the **testing/** directory will use these functions in addition to their application logic to create complete executable programs.
+You will also notice there are function prototypes for these node library functions in the **node.h** header file, located in the **inc/** subdirectory, which you'll notice all the related programs you'll be playing with in this project are **#include**ing.
+The prototypes (taken right from **inc/node.h** are as follows:
+<code c>
+Node *mknode(int   );     // allocate new node containing value
+Node *rmnode(Node *);     // deallocate node
+Node *cpnode(Node *);     // duplicate node
+</code>
+This is your API for the node library. In order to use the node library three things need to happen:
+  * you must **#include "node.h"** (generally already done you in this project)
+  * you must link against **lib/libnode.a** (the Makefiles take care of this for you)
+  * you must call the functions providing the appropriate arguments and handling the return values
+In general, this is no different than what you've already done, each and every time you've used **printf()**, **scanf()**, **atoi()**, **sqrt()**, etc. Only until now, you haven't actually had the code  right in front of you. But these functions all work the same way, these conditions have to be met for them to operate and be used.
+The compiler does a lot of behind-the-scenes work (linking against the C standard library by default, so all you have to do is include **stdio.h** and/or **stdlib.h**).
+If you've ever played with the math library, you've had a slightly closer look, as such code wouldn't compile with only an include of **math.h**, you also needed to add a **-lm** on the compiler command-line.
+Again, same details apply here, only the Makefile system automates the library linking. All we have to do is **#include** the appropriate files.
 ====Node library unit tests====
 In **testing/node/unit/**, you will find 3 files (along with a **Makefile**):
@@ Line 317: / Line 340: @@
 This project has you making changes to 3 files, all in the **testing/node/app/** directory:
+  * **node-app-arrtolist.c** - convert an existing array to a linked list
+  * **node-app-display2.c**  - rewrite the list-building logic using a do-while loop
+  * **node-app-test3.c**     - rewrite **-test2** using node library functions
+In addition to the stated tasks, you are to convert the code in these 3 programs to use node library functions (i.e. once complete, you should no longer be calling **malloc()** to create new nodes, and you shouldn't be initializing node values to 0 or setting initial next pointers to NULL-- let the node library functions do that for you).
+=====node-app-test3=====
+A big aspect of the **node0** and **node1** projects is to get you acclimated to the overall structure of the project organization, and to make use of library functions created to facilitate our on-going explorations.
+So, along that path, your task with **node-app-test3** is to re-implement the functionality of **node-app-test2** (previously provided as a complete running program in the **node0** project), and to convert it over to using node library functions.
+That means:
+  * no more explicit **malloc()** calls, value initializations to 0, initial next pointers to NULL; use **mknode()** instead
+  * use of **cpnode()** where you have instances of duplicated nodes (this DOES happen in **node-app-test2**.
+You are to get a program that produces the same functional output (obviously with different displayed addresses), by using the node library and its functions.
+The skeleton is there, you just need to adapt the code.
+=====node-app-arrtolist=====
+As a means of testing your understanding, this program sets up a pre-existing array, filled with values, and displays it to STDOUT.
+Your task is to add in logic that builds a list, one node at a time, containing the same values (and in the same order) as is found in that array, and to then display the linked list to STDOUT, where we should see identical information.
+Sample output of completed code should look like:
 <cli>
- -> 17 -> 23 -> 4 -> 56 -> 2 -> NULL
+lab46:~/src/data/node1/bin$ ./node-app-arrtolist
+Array: 3 1 4 1 5 9 2 6 5 3 5 8 9 7
+List:  3 1 4 1 5 9 2 6 5 3 5 8 9 7
+lab46:~/src/data/node1/bin$
 </cli>
-It needs to work for whatever values are put in the list (which can range from 0 to infinite values).
+As the array is defined with set values, your output, when complete and correct, should always be the same. This tends to be a good exercise in demonstrating you understand conceptually what is going on and can perform the necessary node manipulations to pull it off.
+Again, be sure to use node library functions (like **mknode()**) in this program.
+=====node-app-display2=====
+In the **node0** project we had to implement the display functionality for the list being built.
+Here, we work with that same idea, only we change a few things around structurally in the program- the final output should still be the same, but the code to produce it will be different.
+Basically, there are three items for you to address:
-You need to display the node's contents, and separate that from the next bit of information with a space separated "->", to help show the continuity of nodes we've joined together.
+  * convert your raw **malloc()** calls and node initializations to **mknode()** calls. There should be 0 instances of **malloc()** in your final code.
+  * switch the main driving loop that builds the list to a **do-while** (the previous version used a **while**). But you're aiming for the same end result.
+    * your display functionality can remain a **while**
+  * move your display code into a dedicated **display()** function, which takes as a parameter a Node pointer pointing to the preferred beginning of the list you'd like to display.
+    * This starts warming us up to future projects, where we'll be using and calling lots of functions
-Finally, when you have exhausted your list, display a terminating "NULL" to visually signify the completion of the task.
+The output should be the same as experienced in **node-app-display**, the first version of the program, as you had to complete in the **node0** project.
 =====Submission Criteria=====
@@ Line 332: / Line 397: @@
   * Code must compile cleanly (no warnings or errors)
+    * **node-app-test3**, **node-app-arrtolist**, and **node-app-display2**
   * Executed programs must display in a manner similar to provided output
   * Processing must be correct based on input given and output requested

Lab46 Wiki

User Tools

Site Tools

Differences

Page Tools