programming-for-dummies

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Python Data Structures
One unique feature of Perl arrays is that you can use arrays to mimic a stack
data structure with Perl’s push and pop commands. To push a new item
onto an array, you can use the push command:
push(@arrayname, item2add);
To pop an item off the array, use the pop command like this:
$variablename = pop(@arrayname);
Creating a Perl hash array
A hash array stores an item along with a key. Perl offers two ways to store
values and keys. The first is like this:
%hasharray = (
key1 => value1,
key2 => value2,
key3 => value3,
);
Notice that hash arrays are identified by the percentage (%) symbol.
A second way to define a hash array is like this:
%hasharray = (“key1”, value1, “key2”, value2, “key3”,
value3);
To retrieve data from a hash array, you need to know the key associated with
that value and identify the hash array name by using the $ symbol like this:
$variable = $hasharray (“key1”);
The preceding command would store the value associated with “key1” into
the $variable.
Python Data Structures
Python offers tuples, lists, and dictionary data structures. Both tuples and
lists contain a series of items, such as numbers and strings. The main difference
is that items in a tuple can’t be changed whereas items in a list can be
changed. A dictionary stores values with keys, allowing you to retrieve
values using its distinct key.