The program allows users to enter reminders for specific days and display a calendar visually indicating which days have associated reminders.

This is a multi-file C program that consists of three files:

• main.c (the main file where the main function exists),
• reminder.c (the implementation file containing functions for inserting reminders into the calendar and displaying the calendar,
• reminder.h (the header file defining a struct named Month, constants, and function prototypes).

The calendar should visually indicate which days have reminders using parentheses (dd) for days with reminders. The user should be able to view the updated calendar and the list of reminders after each reminder entry.

The Month struct in the given header file stores reminders in a variable named November which is declared as a global variable in the main.c.