#!/usr/bin/perl -wl

use strict;

my @A = ( -5, 3, 1, -2 );

my $acc = 0;

for my $i ( 0 .. @A - 2 ){
	$acc += abs( $A[ $i ] - $A[ $i + 1 ] );
	}

print $acc;

$acc = 0;

( ',' x ( @A - 1 ) ) =~ /
	.
	(?{
		$acc += abs( $A[ $-[0] ] - $A[ $-[0] + 1 ] );
		})
	(*FAIL)
	/x;

print $acc;