Solutions to Lab 8
------------------

1. Here's a gawk script:

NR == 1 {
    saved = $0
    print $0
    next
}
{
   if (saved == $0) {
       next
   } else {
       print $0
       saved = $0
   }
}

2. Here's a gawk script:

{
   if (store[$0] == 1) {
   } else {
      print
      store[$0] = 1
   }
}

3. sort +2 -3 +0 +1 -2 +3 oldphonenumbers.txt
                                                                                
In the above command, the "+1" and "+3" parts are not absolutely necessary
but it is good to be pedantic and make our intentions clear to a fellow
programmer.