UP | HOME

Pointers Project
COP-3223H

Table of Contents

1. Overview

In this project, you will implement a linked list and several functions that operate on them.

2. Repository setup

Log into eustis: 

ssh NID@eustis.eecs.ucf.edu

Go to your local repository: Be sure you have already completed the git exercise before attempting this project. 

cd ~/cop3223spring26/assignments

Create and enter a directory for the pointers project: 

mkdir pointers
cd pointers

You only need to mkdir once to create the directory.

Make sure you are in the right directory 

pwd

You should see 

/home/net/NID/cop3223spring26/assignments/pointers

3. Create the pointers project

Make sure you are in the right directory 

pwd

You should see 

/home/net/NID/cop3223spring26/assignments/pointers

3.1. The linked list template program

wget https://www.cs.ucf.edu/~gazzillo/teaching/cop3223hspring26/files/template.c
mv template.c pointers.c

#include <stdio.h>
#include <assert.h>
#include <malloc.h>
#include <stddef.h>
#include <stdbool.h>

struct list {
  int data;
  struct list *next;
};

struct list *add(struct list *head, int data) {
  struct list *newlink;

  newlink = malloc(sizeof(struct list));
  newlink->data = data;
  newlink->next = head;

  return newlink;
}

void print(struct list *head) {
  if (NULL == head) {
    printf("()");
  } else {
    printf("(%d,", head->data);
    print(head->next);
    printf(")");
  }
}

void deleteall(struct list *head) {
  if (NULL == head) {
    // do nothing
  } else {
    deleteall(head->next);
    free(head);
  }
}

// get the length of the list, 0 if NULL
int len(struct list *head) {
  // TODO
}

// return the list element that contains data or NULL if none
struct list *get(struct list *head, int data) {
  // TODO
}

// return head or next if head is being deleted or NULL if empty going in or out
struct list *del(struct list *head, int data) {
  // TODO
}

int main(int argc, char **argv) {
  struct list *head;
  bool done = false;

  head = NULL;

  do {
    char c;
    int value;
    int retval;
    printf("enter a command (type h for help): ");
    retval = scanf(" %c", &c);
    done = done || EOF == retval;
    /* printf("command: %c\n", c); */
    switch (c) {
    case 'p':
      printf("current list: ");
      print(head);
      printf("\n");
      break;
    case 'a':
      printf("enter an integer value: ");
      retval = scanf("%d", &value);
      done = done || EOF == retval;
      head = add(head, value);
      break;
    case 'l':
      printf("length: %d\n", len(head));
      break;
    case 'g':
      printf("enter an integer value: ");
      retval = scanf("%d", &value);
      done = done || EOF == retval;
      printf("found list: ");
      print(get(head, value));
      printf("\n");
      break;
    case 'd':
      printf("enter an integer value: ");
      retval = scanf("%d", &value);
      done = done || EOF == retval;
      head = del(head, value);
      printf("new list: ");
      print(head);
      printf("\n");
      break;
    case 'D':
      deleteall(head);
      head = NULL;
      printf("deleted all\n");
      break;
    case 'h':
      printf("instructions:\n");
      printf("p - print the list\n");
      printf("a - add a link\n");
      printf("l - report the current length\n");
      printf("g - get a link\n");
      printf("d - delete a link\n");
      printf("D - delete the whole list\n");
      printf("h - help\n");
      printf("q - quit\n");
      break;
    case 'q':
      done = true;
      break;
    default:
      printf("invalid command\n");
      break;
    }
  } while (! done);

  printf("bye!\n");
}

3.2. Example inputs and outputs

Here is a complete sessions that uses all the features. 

enter a command (type h for help): a
enter an integer value: 4
enter a command (type h for help): a
enter an integer value: 43
enter a command (type h for help): a
enter an integer value: 87
enter a command (type h for help): a
enter an integer value: 78
enter a command (type h for help): p
current list: (78,(87,(43,(4,()))))
enter a command (type h for help): l
length: 4
enter a command (type h for help): g
enter an integer value: 78
found list: (78,(87,(43,(4,()))))
enter a command (type h for help): d
enter an integer value: 78
new list: (87,(43,(4,())))
enter a command (type h for help): p
current list: (87,(43,(4,())))
enter a command (type h for help): D
deleted all
enter a command (type h for help): l
length: 0
enter a command (type h for help): a
enter an integer value: 1
enter a command (type h for help): p
current list: (1,())
enter a command (type h for help): q
bye!

3.3. Program name

The program must be called pointers.c and must be in the pointers directory, i.e., the full path should be 

~/cop3223spring26/assignments/pointers/pointers.c

Compile and run the program whenever you make changes using 

cd ~/cop3223spring26/assignments/pointers/
gcc -o pointers pointers.c
./pointers

Be sure there is no other output besides the required output as the grading will be automatic. If you would like to have debugging output, use fprintf(stderr, "...", ...); instead of printf.

4. Submitting your program via git

This assumes you have already setup your repository and that you are still in your hello directory in your repository.

4.1. Add and commit the file

Enter 

git add pointers.c
git commit pointers.c

Write an appropriate commit message. Remember that you will need to save (Ctrl-x Ctrl-s) then quit (Ctrl-x Ctrl-c) the emacs editor that pops up. If you are having trouble, be sure that you have completed the git project first.

Do not commit the backup file pointers.c~ nor the pointers program. Use a .gitignore file to exclude those from the repository, so they won't show up when you type git status.

Then to synchronize the changes to the remote git repository on the grading server: 

git push

5. Self-check

5.1. Remove the previous self-check

If you have already run the self-check, you can remove it like this 

rm -rf ~/tmp/assignments_selfcheck

Double-check the path carefully to avoid deleting the wrong directory.

5.2. Make a fresh clone of your project

git clone gitolite3@eustis3.eecs.ucf.edu:cop3223/$USER/assignments ~/tmp/assignments_selfcheck

You should see something like 

Cloning into '/home/net/NID/tmp/assignments_selfcheck'...

Welcome to eustis.eecs.ucf.edu.

Please use your NID and NID password to log in.

See http://t.cs.ucf.edu/help/eustis  for additional instructions.

remote: Enumerating objects: 16, done.
remote: Counting objects: 100% (16/16), done.
remote: Compressing objects: 100% (12/12), done.
remote: Total 16 (delta 1), reused 0 (delta 0), pack-reused 0
Receiving objects: 100% (16/16), done.
Resolving deltas: 100% (1/1), done.

If you see 

fatal: destination path '/home/net/NID/tmp/assignments_selfcheck already exists and is not an empty directory.

then remove the previous self-check.

5.3. Enter the fresh clone's directory

cd ~/tmp/assignments_selfcheck/pointers

5.4. Make sure pointers runs correctly

cd pointers
gcc -o pointers pointers.c
./pointers

6. Grading schema

Criterion Points
pointers.c exists and compiles 1
The program runs correctly, prorated by successful test cases 3
TOTAL 4

Author: Paul Gazzillo

Created: 2026-04-29 Wed 10:21

Validate