Capstoneintermediate6h

C Contact Book

Design (on paper/in guided steps, since this platform can't execute C) a command-line contact book in C, applying structs, arrays, pointers, and manual memory management.

Tracks: C Programming

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Objectives

Design a Contact struct (name, phone, email) and a dynamically-resizable array of contacts using malloc/realloc
Write functions to add, search (by name), and remove a contact, passing the contact array by pointer
Free all allocated memory correctly before the program exits, with no leaks
Read/write the contact list to a text file so data survives between runs

Before you start

Milestones

1. Design the Contact struct and storage

Define a Contact struct and a dynamically-growable array to hold contacts.

Contact struct has at minimum name, phone, and email fields
The contact array grows via malloc/realloc as contacts are added, not a fixed-size array

2. Add and search functions

Write add_contact and find_contact(name) functions operating on the array via a pointer.

add_contact grows the array if it's full before inserting
find_contact returns a clear 'not found' signal (e.g. NULL or -1) rather than undefined behavior

3. Remove a contact without leaking or corrupting memory

Write remove_contact(name) that shifts remaining entries and never double-frees.

Removing a contact doesn't leave a gap or duplicate entry in the array
No memory is freed twice, and no already-freed memory is accessed afterward

4. Persist to a file and clean up

Save/load the contact list to a text file, and free all memory before exit.

Contacts saved on exit can be reloaded correctly on the next run
Every malloc'd block is freed exactly once before the program ends

References

cppreference: C