After much fiddling around I have arrived at the following: 
#!/usr/bin/perl -w
#use strict;
use CGI ':standard';

my @db = (1, 3, 5, 7, 9, 11);
my @in = (1, 2, 5, 8, 9, 10, 13);
my $var = 7; # I have this variable available to indicate the length o
+f the array
my (%db_lookup, %in_lookup);
@db_lookup{@db} = ();
@in_lookup{@in} = ();



$count = 0;
while ($count < $var) {
     if (exists $in_lookup{$count}, @db) {
      @db = grep { not exists $in_lookup{$_} } @db;
      $count += 1;
      } elsif (not exists $in_lookup{$count}, @db) {
      push @db, grep { not exists $db_lookup{$_} } @in;
      $count += 1;
}
}
      
      print "view: @db";

[download]
That does what I need when strings match. However when strings don't match the db is unchanged from the original, wheras I need the contents of @in pushed into @db: 

my @db = (1, 3, 5, 7, 9, 11);
my @in = (21, 22, 25, 28, 29, 210, 213);

[download]
Where am I going wrong?

In reply to Re: Re: Help needed to make a conditional statement by jonnyfolk
in thread Help needed to make a conditional statement by jonnyfolk

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