Just as Rata mentioned, a hash is more logical a solution in this case, a very simple hash approach can perform the job quite efficiently...

how do i compare the array data?...

Using a hash you don't have to compare data because all you need is just a hash key to hold all the data that belong to that type of fruit...

Consider

use strict;
use warnings;
use Data::Dumper;
my %hash;
while(<DATA>){
    my ($key, $number)=split;
    $hash{$key} +=$number;
    }

print Dumper (\%hash);
__DATA__
apples 10
oranges 3
apples 3
oranges 7
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