@ACCTS = ("1234", "5678", "6959");
open(IN,"InFile.txt");
%acct="";
while (defined($line = (<IN>))){
  foreach $x (@ACCTS) {
     if ($line =~/$x/){
   	$acct{$x} = ($x,$line);
     }
  }
}

foreach $key (sort keys %acct){
   print "$acct{$key}\n";
}