POJ 算法练习题 2-2

#!usr/bin/perl

use strict;
use warnings;
# use POSIX;
use 5.010;

                # my $my_test =("A"==0);
# print $my_test;

sub input_check {

    my ($x1, $x2, $y1, $y2);
    my @num_of_steps;

    # devide input to get coordinates;
    for (@_) {
        $_ = uc($_); #Capitalized the string;
        
        # a simple check if input is valid
        if(length($_) != 6) {
            $x1 = "0";
            $y1 = "0";
            $x2 = "0";
            $y2 = "0";
        } # This exception would be treated later.
        else {
            $x1 = substr $_, 0, 1;
            $y1 = substr $_, 1, 1;
            $x2 = substr $_, 3, 1;
            $y2 = substr $_, 4, 1;
        }
        
        # print join(" ",$x1,$x2,$y1,$y2);
        # check if points are in the same straight line
        my $same_stra_line;
        if (($x1 eq $x2) || ($y1 == $y2)){
            $same_stra_line = 1;
        }
        else {
            $same_stra_line = 0;
        }
        
        # check if points are in the same skew line
        my $same_skew_line;
        if ((ord($x1)-ord($x2)) == ($y1-$y2)){
            $same_skew_line = 1;
        }
        else {
            $same_skew_line = 0;
        }
        
        # check if points are in the same while/black zone
        my $same_zone;
        # $same_skew_line = (((ord($x1)%2) xor ($y1%2)) == ((ord($x2)%2) xor ($y2%2)));
        if (((ord($x1)%2) xor ($y1%2)) == ((ord($x2)%2) xor ($y2%2))){
            $same_zone = 1;
        }
        else {
            $same_zone = 0;
        }
        
        # calculate the max distance
        my $max_dist;
        $max_dist = (abs(ord($x1)-ord($x2)))>= (abs($y1-$y2))? abs(ord($x1)-ord($x2)):abs($y1-$y2);
        
        if($x1 eq "0"){
            push @num_of_steps, "invalid input";
        }
        else {
            push @num_of_steps, join(" ", $max_dist, ($same_stra_line || $same_skew_line)?1:2, $same_stra_line?1:2, ($same_zone?($same_skew_line?1:2):"Inf"));
            # push @num_of_steps, $max_dist." ".$same_stra_line." ".$same_skew_line." ".$same_zone;
        }
    }
    @num_of_steps;  
}

my @coor_input;
my @coor_output;
print "Please input a number of coordinates!\n";
@coor_input = (<STDIN>);
# @coor_input = ("A2 E4");
@coor_output = input_check(@coor_input);
print "@coor_output\n";