# wages - An example program to illustrate some of the 
#            features of Perl
#  Input: A file of lines of employee data, where each line has
#         name:age:department code:salary
# Output: 1. The names of all employees whose names end with "son"
#         2. Percentage of employees under 40 years old
#         3. Average salary of employees under 40 years old
#         4. An alphabetical list of employees who are under 40
#            years old and who have salaries more than $40,000

# Open the data file and display a header for employees 
#  whose names end in 'son'

open(EMPLOYEES, "employees") || die "Can't open employees $!";
print("Names that end in 'son'\n\n");

# Loop to read and process the employee data

while (<EMPLOYEES>) {

# Increment the number of employees and chop off the newline

    $total_employees++;
    chomp;

# Split the input line into its four parts

    ($name, $age, $dept, $salary) = split(/:/);

# If the name ends in 'son', print the name

    if ($name =~ /son$/) {
        print ("$name \n")
    }

# If the employee is under 40, count him or her and add his or her
#  salary to the sum of such salaries

    if ($age < 40) {
        $under_40++;
        $salary_sum += $salary;

# If the salary was over 40,000, add the person and his or her 
#  salary to the hash of such people

        if ($salary > 40_000) {
            $sublist{$name} = $salary
        }
    }
}

# If there was at least one employee, continue

if ($total_employees > 0) {
 
# Process and display the results for those under 40
  
    if ($under_40 > 0) {

# Compute and display the % of employees under 40 and their
#  average salaries

        $percent = 100 * $under_40 / $total_employees;
        print ("\nPercent of employees under 40 is: $percent \n");
        $avg = $salary_sum / $under_40;
        print ("Average salary of employees under 40 is: $avg \n");

# Sort and display the names of the employees under 40

        print ("Sorted list of employees under 40",
               " with salaries > \$40,000 \n");
        @sorted_names = sort (keys(%sublist));
        print ("\nName \t\t Salary\n");
        foreach $name (@sorted_names) {
            print ("$name \t \$$sublist{$name} \n")
        }
    }
    else {
        print ("There are no employees under 40 \n")
    }

    
}
else {
    print ("There were no employees\n")
}