CS 1511 (Fall 1998-1999) Program 5

Computer Science 1511
Computer Science I

Programming Assignment 5
Conditions and Loops (35 points)
Due Thursday, November 11, 1999

Introduction

This assignment will provide you with practice both on conditions and loop statements. You should structure your program into procedures and functions performing single functions and test your program one subprogram at a time using drivers.

The Problem

The DatesRUs calendar company has decided to write a calendar program to generate calendars for years between 1800 and 2399. They want you to produce a program that prompts a user for a month (entered as a number between 1 and 12) and a year (entered as a number between 1800 and 2399) and then have the program print out a calendar for that month in that year. Samples of the output of the program are shown below:

-------------------------------------------------
Welcome to the DatesRUs Calendar program!

This program will prompt you for a month and year
and will print a calendar for that month.  To
enter the month you will type a number between
1 and 12 representing the months January (1),
February (2), March (3) and so on.  The year
must be a number between 1800 and 2399.


Enter month (1-12) of calendar to print: 1
Enter year (1800-2399) of month to print: 1800

January 1800

Sat  4 11 18 25 
Fri  3 10 17 24 31 
Thu  2  9 16 23 30 
Wed  1  8 15 22 29 
Tue     7 14 21 28 
Mon     6 13 20 27 
Sun     5 12 19 26
-------------------------------------------------
Welcome to the DatesRUs Calendar program!

This program will prompt you for a month and year
and will print a calendar for that month.  To
enter the month you will type a number between
1 and 12 representing the months January (1),
February (2), March (3) and so on.  The year
must be a number between 1800 and 2399.


Enter month (1-12) of calendar to print: 2
Enter year (1800-2399) of month to print: 1900

February 1900

Sat  3 10 17 24 
Fri  2  9 16 23 
Thu  1  8 15 22 
Wed     7 14 21 28 
Tue     6 13 20 27 
Mon     5 12 19 26 
Sun     4 11 18 25
-------------------------------------------------
Welcome to the DatesRUs Calendar program!

This program will prompt you for a month and year
and will print a calendar for that month.  To
enter the month you will type a number between
1 and 12 representing the months January (1),
February (2), March (3) and so on.  The year
must be a number between 1800 and 2399.


Enter month (1-12) of calendar to print: 3
Enter year (1800-2399) of month to print: 2001

March 2001

Sat  3 10 17 24 31 
Fri  2  9 16 23 30 
Thu  1  8 15 22 29 
Wed     7 14 21 28 
Tue     6 13 20 27 
Mon     5 12 19 26 
Sun     4 11 18 25
-------------------------------------------------
Welcome to the DatesRUs Calendar program!

This program will prompt you for a month and year
and will print a calendar for that month.  To
enter the month you will type a number between
1 and 12 representing the months January (1),
February (2), March (3) and so on.  The year
must be a number between 1800 and 2399.


Enter month (1-12) of calendar to print: 0
Please use a number between 1 and 12!
Enter month (1-12) of calendar to print: 13
Please use a number between 1 and 12!
Enter month (1-12) of calendar to print: 15
Please use a number between 1 and 12!
Enter month (1-12) of calendar to print: -2
Please use a number between 1 and 12!
Enter month (1-12) of calendar to print: 12
Enter year (1800-2399) of month to print: 2400
Please use a number between 1800 and 2399!
Enter year (1800-2399) of month to print: 0
Please use a number between 1800 and 2399!
Enter year (1800-2399) of month to print: 239 9
Please use a number between 1800 and 2399!
Enter year (1800-2399) of month to print: Please use a number between 1800 and 2399!
Enter year (1800-2399) of month to print: 2399

December 2399

Sat  4 11 18 25 
Fri  3 10 17 24 31 
Thu  2  9 16 23 30 
Wed  1  8 15 22 29 
Tue     7 14 21 28 
Mon     6 13 20 27 
Sun     5 12 19 26
-------------------------------------------------

Program Notes

You must prompt the user for input until the month and year values are valid.
January 1 in the year 1800 falls on a Wednesday.
For the period 1800-2399, any year that is evenly divisible by four is a leap year except for the years 1800, 1900, 2100, 2200, and 2300. You can test if a number is evenly divisible by four using the % (remainder) operator and a relational operator.
In leap years, there are 366 days in a year, with February having 29 days. In non-leap years, there are 365 days in a year, with February having 28 days.
January, March, May, July, August, October, and December have 31 days.
April, June, September, and Novemeber have 30 days.
If you know the day of the week (1-7 for Sunday to Saturday) for the first of January in year X you can find out what day of the week the first of January for year X+1 falls on using the following process (assume Jan1Day is currently the day of the week January 1 falls on in year X):
```
     if (Year X is a leap year)
       Jan1Day += 366;
     else
       Jan1Day += 365;
     Jan1Day = Jan1Day % 7;
     if (Jan1Day == 0)
       Jan1Day = 7;
```
Jan1Day now is the day of the week January 1 in year X+1 falls on. Note, you will have to fill in the appropriate test for determining if Year X is a leap year in the above code.
You must NOT simply use a giant switch statement to print out the calendar.

Since your program will be heavily modularized, be sure to test each procedure individually as you progress.

What To Hand In

Hand in a full lab report for your program. For your tests you should show the enough different combinations of month and year to conclude that your program produces the correct output for all of the month and year combinations.

EXTRA CREDIT

(7 points) When the user types 0 for the month, print out a calendar for the entire year with three columns of months (and four rows). The format of the full year calendar would be: