Lama example, 5th edition, page 41, Special Array Indices

First an array is introduced:

$rocks[0] = 'bedrock';      #One element...
$rocks[1] = 'slate';        #another...
$rocks[2] = 'lava';         #and another...
$rocks[3] = 'crushed rock'; #and another...
$rocks[99] = 'schist';      #now there are 95 undef elements
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then there's

$end = $#rocks;                #99, which is the last element's index
$number_of_rocks = $end + 1    #okay, but you'll see a better way late
+r
$rocks[$#rocks] = 'hard rock'  #the last rock
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I thought, because I didn't quite see what the sudden appearance of $number_of_rocks meant, that somehow a new index was being tacked on at the end of the array, and then given the value of 'hard rock'. I didn't realise that 'schist' was no more and that it's $rocks[99] = 'hard rock'.

Niet een slimme poes.

#!/usr/bin/perl
use strict;
use warnings;
print "Type in a string: \n";
chomp ($string = <STDIN>);
$string.=' ';
print "Type in a number: \n";
chomp ($int = <STDIN>);
if ($int >= 100) {
  print "Whoa, too big man.\n";
} else {
  print "The result is \n", $string x $int,"\n";
}
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