Shell Programming and Scripting

my @arcb= (450,625,720,645); 
my @arca=(625,645);



foreach my $a (@arca){
for(my $i=0;$i<scalar(@arcb);$i++){
delete $arcb[$i] if($a==$arcb[$i]);
    }
}
my $length = @arcb;
print "@arcb";
print "length is $length \n";

$ IFS=$'\n'; echo "${arcb[*]}"|grep -v "${arca[*]}"
450
720

               Deleting an array element effectively returns that position of
               the array to its initial, uninitialized state.  Subsequently
               testing for the same element with exists() will return false.
               Also, deleting array elements in the middle of an array will
               not shift the index of the elements after them down.  Use
               splice() for that.  See "exists".

#!/usr/bin/perl
use strict;
 
my @arcb=(450,625,720,645);
my @arca=(625,645);
my @arcc;
 
foreach my $b (@arcb) {
  my $flg=0;
  foreach my $a (@arca) {
    if($a==$b) {
      $flg=1;
      last;
    }
  }
  push(@arcc,$b) if($flg==0);
}
 
@arcb = @arcc;
 
my $length = @arcb;
print "@arcb";
print "length is $length \n";