fig20_07.pl

来自「PERL语言资料 可以用于PERL程序设计」· PL 代码 · 共 49 行

#!/usr/bin/perl
# Figure 20.7: fig20_07.pl
# Using a doubly-linked list.

use warnings;
use strict;
use DoublyLinkedList;

my $dll = new DoublyLinkedList();

for ( 1 .. 5 ) {
   $dll->insertNode( $_ );
}

print( "The list contains:\n" );
$dll->printAll();   # display list contents
print( "\nThe head is ", $dll->gotoHead(), ".\n" );

$dll->nextNode();       # move to next node
$dll->deleteNode();     # delete node at current position
$dll->nextNode();       # move to next node
$dll->deleteNode();     # delete node at current position
print( "\nAfter deleting two elements, ",
       "The list contains:\n" );
$dll->printAll();   # display list contents

print( "\nNow at ", $dll->data(), ".\n" );
print( "Now at ", $dll->previousNode(), ".\n" );
print( "Now at ", $dll->previousNode(), ".\n" );

print( "Attempting to go before the first list element:\n" );
$dll->previousNode();

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