fig04_08.pl

PERL语言资料 可以用于PERL程序设计

#!/usr/bin/perl
# Fig. 4.8: fig04_08.pl
# Manipulating the length of an array.

@array = 
   qw( zero one two three four five six seven eight nine );

# output the number of elements and the last index number
print "There are ", scalar( @array ), 
      " elements in \@array.\n";
print "The last index in \@array is $#array.\n\n";

# output the last element in the array
print "\@array[ $#array ] is $array[ $#array ].\n\n";

# use negative subscripts to access 
# elements from the end of the array
print "\@array[ -1 ] is $array[ -1 ].\n";
print "\@array[ -4 ] is $array[ -4 ].\n\n";

$#array = 5;         # reduce the number of elements to 6
print "@array.\n";

$#array = 10;        # increase the number of elements to 11
print "@array.\n";

@array = ();         # remove all elements in the array
print "@array.\n";
print "There are now ", scalar( @array ), 
      " elements in \@array\n";

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