Use hashes: 
#!/usr/bin/perl
use warnings;
use strict;

my @Array_1 = qw(a1 a2 a3 a4 a5 a6);
my @Array_2 = qw(a1 b2 c3 a4 f5 a6);
my @Array_3 = qw( 1  2  3  4  5  6);

# convert to hashes
my (%h1, %h2, %h3);
undef @h1{@Array_1};
my @idxs = 1 .. @Array_1;
@h2{@Array_2} = @idxs;
@h3{@idxs}    = @Array_3;

# do the calculations
my %h_tmp = %h2;
delete @h_tmp{@Array_1};
delete @h2{keys %h_tmp};

# output
($,, $\) = (' ', "\n");
print keys %h2;
print @h3{values %h2};

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In reply to Re: Match speed of R in array procesing by choroba
in thread Match speed of R in array procesing by Anonymous Monk

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