My question in Perl using simple hashes is:
Read a series of employee numbers and daily working hours from standard input, one set perl line.The employee number and the hours worked should be separated by a space. Use hashes and calculate the total number of hours worked and the average number of hours per work period. Print out a report by sorted employee number, the number of work periods, the total hours worked, and the average number of hours per work period. Assume that some of the employees are on a part-time schedule and do not work the same number of days or hours as regular employees.
My code is:

`#!/usr/bin/perl
use strict;
use warnings;
my @series = qw(41234 9 67845 8 32543 10 84395 7 57543 9 23545 11 2354
+5 1 23545 2 23545 6);
my $total_periods = 0;
my $total_hours = 0;
my %empwork;
while (my $series = shift @series)
{
my $nums = shift @series;
$empwork{$series} += $nums;
}
print "Sorted Employee Numbers:\n";
foreach my $empnum(sort keys %empwork)
{
my $periods=0;
$periods++;
my $hours = 0;
$hours += $empwork{$empnum};
my $avg = $hours/$periods;
$total_periods += $periods;
$total_hours += $hours;
print "$empnum\n$periods periods\n$hours hours\n$avg average\n\n";
}
my $grand_avg = $total_hours/$total_periods;
print "The number of work periods is $total_periods\n";
print "Total number of hours is $total_hours\n";
print "Average number of hours per work period is $grand_avg\n";
`

I am not getting the exact output. Where am I going wrong? Please help. Thanks in advance.