A Simple Example of Dynamic Programming using perl scripts

#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my @stations = ([2,7,9,3,4,8,4,3], [4,8,5,6,4,5,7,2] ); # 0,1,2,3,4,5,6,7
my @transfer = ([2,3,1,3,4], [2,1,2,2,1] ); # 0,1,2,3,4,5

my (@fastway, @line);

($fastway[0][0], $fastway[0][1]) = ($stations[0][0], $stations[0][0]+$stations[0][1] );
($fastway[1][0], $fastway[1][1]) = ($stations[1][0], $stations[1][0]+$stations[1][1] );
($line[0][0], $line[0][1]) = (0,0);
($line[1][0], $line[1][1]) = (1,1);

for( my $i=2; $i<=6; $i++ ){

        # for line one
        if( $fastway[0][$i-1] <= $fastway[1][$i-1] + $transfer[1][$i-2] ){
                $fastway[0][$i] = $fastway[0][$i-1] + $stations[0][$i];
                $line[0][$i] = 0;
        }else{
                $fastway[0][$i] = $fastway[1][$i-1] + $transfer[1][$i-2] + $stations[0][$i];
                $line[0][$i] = 1;
        }

        # for line two
        if( $fastway[1][$i-1] <= $fastway[0][$i-1] + $transfer[0][$i-2] ){
                $fastway[1][$i] = $fastway[1][$i-1] + $stations[1][$i];
                $line[1][$i] = 1;
        }else{
                $fastway[1][$i] = $fastway[0][$i-1] + $transfer[0][$i-2] + $stations[1][$i];
                $line[1][$i] = 0;
        }

}

$fastway[0][7] = $fastway[0][6] + $stations[0][7];
$fastway[1][7] = $fastway[1][6] + $stations[1][7];

my $line = 0;
$line[$line][7] = $line;
$line[$line][7] = $line = 1 if( $fastway[0][7] >= $fastway[1][7] );

print "StepMarker\tStations\tTimeCost\n";
for( my $i=0; $i<8; $i++ ){

        my $index;
        if( $i==0 ) {
                $index = "EnterTimeCost";
        }elsif( $i==7 ) {
                $index = "TotalTimecost";
        }else{
                $index = "FinishStation";
        }

        print join("\t", "$index$i", $line[$line][$i]+1, $fastway[$line][$i], "\n" );

}

stations = [[2,7,9,3,4,8,4,3], [4,8,5,6,4,5,7,2]]
transfer = [[2,3,1,3,4], [2,1,2,2,1]]

fastway = [ [stations[0][0], stations[0][0]+stations[0][1]], [stations[1][0], stations[1][0]+stations[1][1]] ]
line = [ [0,0], [1,1] ]

for i in range(2,7):

        # for line one
        if fastway[0][i-1] <= (fastway[1][i-1] + transfer[1][i-2]):
                fastway[0].append( fastway[0][i-1] + stations[0][i] )
                line[0].append( 0 )
        else:
                fastway[0].append( fastway[1][i-1] + transfer[1][i-2] + stations[0][i] )
                line[0].append( 1 )

        #for line two
        if fastway[1][i-1] <= (fastway[0][i-1] + transfer[0][i-2]):
                fastway[1].append( fastway[1][i-1] + stations[1][i] )
                line[1].append( 1 )
        else:
                fastway[1].append( fastway[0][i-1] + transfer[0][i-2] + stations[1][i] )
                line[1].append( 0 )

fastway[0].append( fastway[0][6] + stations[0][7] )
fastway[1].append( fastway[1][6] + stations[1][7] )

li = 0
line[li].append( 0 )
if fastway[0][7] >= fastway[1][7]:
        li = 1
        line[li].append( 1 )

print "StepMarker\tStations\tTimeCost"
for i in range(8):

        if i==0: index = "EnterTimeCost"
        elif i==7: index = "TotalTimecost"
        else: index = "FinishStation"
        print ‘%s%d\t%d\t%d‘ % (index, i, line[li][i]+1, fastway[li][i])