#!/usr/bin/env perl

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AUTHOR: Robert DiCicco

DATE:   01-18-2023

Challenge #200 Arithmetic Slices ( Perl )

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use strict;

use warnings;

 

my @out = ();

 

sub GetIntervals {

                my $slice = shift;

                return -1 if (scalar @$slice < 3);

                my $x = 0;

                               

                while ( $x < scalar @$slice ) {

                                if ( $x > 0 ) {

                                                my $interval = $slice->[$x] - $slice->[$x-1];

                                                push(@out, $interval );

                                }

                                $x++;

                }

                my $testval = $out[0];

                for my $arrint (@out) {

                                if ( $arrint != $testval ){

                                                return -1;

                                }

                }

                return 1;

}

 

my @lists = ([1,2,3,4],[2]);

 

for my $list (@lists) {

                my $cnt = 0;

                print("Input: \@array = \[@$list\]\n");

                my @slice = ();

                print("Output: ");

                while( $cnt < scalar @$list - 2) {

                                @slice = @$list[$cnt..$cnt+2];

                                if (scalar @slice == 3) {

                                                my $retval = GetIntervals(\@slice);

                                                if ($retval == 1 ) { print("[@slice] ")};

                                }

                                $cnt++;

                                @slice = ();

                }

                my $ret = GetIntervals(\@$list);

                $ret == 1 ? print("[@$list]\n") : print("()\n");

                print("\n");

}

 

=begin

SAMPLE OUTPUT

perl .\ArithmeticSlices.pl

Input: @array = [1 2 3 4]

Output: [1 2 3] [2 3 4] [1 2 3 4]

 

Input: @array = [2]

Output: ()

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