LecLabs 2.5 Heaps and Paging

Lecture video on the heap

Lecture video on malloc an int

Lecture video on create a heap based array

Lecture video on free the heap

Follow the CODE instructions to define a pointer and allocate memory for an array of 4 integers.

Objective

In this lab, we will create a stack data structure.

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Steps to Complete

1. Modify functions in stack.c to complete the CODE: requests
2. Modify main in main.c to complete the CODE: requests
3. Modify the Makefile to enable compiling
4. Compile and test the program
5. Run /challenge/tester
6. Get flag

Lecture video on relloc

Lecture video on getline

Lecture video on strdup

Lecture video on struct alloc

Follow the CODE instructions to create a heap based array of structs.

SPECIAL NOTE: This lab is a part of a series 2.4.1.5 Songs List -> 2.4.2.6 Make Songs -> 2.4.2.6 filter songs. You must first complete 2.4.2.6 Filter Songs before you can start on this lab.

Objective

In this lab, we will create a new version of the song list program where the results are filtered and paginated.

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Requirements

1. Create paging for full list
• Declare a starting index variable
• Wrap the printing for loop in an while that terminates when the user inputs a 'q'
• Change the for loop that prints songs so that it only display 10 songs
• Below the for loop, add a user input prompt printf("(n for next, p for prev, f for filter, q for quit): ");
• Get the user's choice
• if next then increase starting index by 10 as long as it will not exceed the last song's index
• if prev then decrease starting index by 10 as long as it will not make it go below 0
2. Add filtered pagination
• Once the list is filtered, it breaks the next and previous functionality.
• moving to next, requires the code to know when a song is being displayed and keeping track of the number of songs displayed
• To solve this problem, the program will implement a stack that stores the last starting index
  • Pushes the current starting index onto the stack when the user chooses next and then increments it
  • Pops the top most (last pushed) index when the user choose previous and uses it as the starting index
• The function should not repeat entries (e.g., at the end of the list it shold not keep adding the last starting index)
• If the stack is empty it should set the starting index to 0

Steps to Complete

• Implement the requirements
• Compile and test the program
• Run /challenge/tester
• Get flag