#!/usr/bin/perl

################################################

# day_print.pl
# Version 1

# Robert D. Cormia
# UCSC Programming for Bioinformatics II
# October 10, 2003

################################################


# Write a Perl program called 'day_print' to do the following:
#     a. Define a hash called 'days' with 'Mon' => 'Monday', ... 'Sun' =>
#         'Sunday' as the Key-Value pairs
#     b. Use the function 'localtime' to assign a scalar called $date_time
#          with the current date. localtime returns a string like this:
#                                Thu Oct  4 11:02:05 2001
#         (the Day, Mon, Date, Time, Year elements are separated by 1 space)
#     c. From this scalar using the 'split' function find out the current day
#     d. Use this day as a key in the hash 'days' and print the value as
#         'Today is a nice Monday or Tuesday or ...' as the case maybe
#     e. Fetch the year from $date_time and calculate the age of Jon who is
#          born in 1975. Print it.
#

use strict;

my %day_names;
my $date_time;
my @date;
my $day;
my $age;
my $year;
my $year_born;

# Create day_names hash

%day_names = (
		'Mon' => 'Monday', 'Tue' => 'Tuesday', 'Wed' => 'Wednesday',
		'Thu' => 'Thursday', 'Fri' => 'Friday', 'Sat' => 'Saturday',
		'Sun' => 'Sunday'
		);

# Calculate local time using local_time function

$date_time = localtime();

print "Today's local time is $date_time\n";

# Determine day from date_time using split

# Create array for date using @day = split(' '$date_time);

@date = split(' ', $date_time);

# Use first position in the @date array to determine day of week

$day = $date[0];

print "Today's abreviated day is $day\n";

# Use abrev. day from $day to access full name of day from %day_names

print "Today is a nice $day_names{$day}\n";

# Determine $year from date_time using split

# $year is the fifth position in the array @days

#
# Calculate age of Joe from date_time using split
#

# $year will equal the last position in the array @date

$year = $date[4];

print "Today's year is $year\n";

# Joe was born in 1950. $year_born = '1950'

# Year is the fifth element in array @date

# Joe's age = $days[4] - $year_born.

$year_born = '1950';

$age = $year - $year_born;

print "Joe's age is $age years old\n";

__END__