Perl Tutorial - 7: Adding & Removing Array Elements Video Lecture | Perl Building Blocks: An Introduction to Perl - Back-End Programming

hello guys welcome to my channel this is
the seventh video in this course and in
this video we are going to continue our
discussion on operations that we can
perform on arrays in Perl so I have a
script opened up in my IDE
it's called array underscore add remove
and as you can guess from the name we're
gonna check out statements or commands
that we can run in Perl to add or remove
elements from a pre-existing array
variables so on line number three in the
script I have created an array variable
called players and it has two values
Roger and Andy now let's say you want to
add another element or another name to
this array variable players and you want
to end it at the end
right that is after Andy's name you want
to put another tennis players name let's
say that tennis player is Rafa so the
statement that you are going to use or
the command that you're going to use to
do that is called push and you know just
to see the state of the players variable
before we perform the push operation I
have a print statement on line number
five that's just going to print the
contents of the player's variable before
messing up with it and then on line
number seven I have the push statement
and the syntax of the push statement is
really simple you type in the word push
and within a set of parentheses you
first have to pass the name of the array
variable in which you want push an item
and that in our case would be players
and of course you have to put the at the
rate symbol along with the name of the
variable and then you have to put a
comma and then you have to put the item
that you want to push in the list so
that in our case for the time being
let's say is Rafa and you have to put a
semicolon at the end to terminate the
statement just as you do with all the
other statements in perl and let's say
the variable that we now have is version
2 of the player's ray variable so we're
going to
confirm whether the addition was made
successfully or not with a print
statement that we have on line number
eight so this one's first going to
display the text player set two and then
it's going to just display the contents
of the player's variable now let's say
you want to add one more name to this
list but you want to add that name not
to the end of the variable but to the
beginning of the variables so the the
statement that you used to do that is
called unshipped so unlike push and
shift the adds an item at the beginning
of the variable instead of the end and
the syntax though is the same so you
have the name of the variable as the
first argument and the second argument
is the item that you want to put at the
beginning and let's say we want to add
Novak's name to the list so add players
comma Novak is going to put Novak's name
at the beginning of the list again I
have a print statement on line number 11
to see the contents of the player's
variable just to confirm whether the
addition has been made on line number 13
we are going to remove an element from
this player's variable and we're going
to remove the element at the end of the
the list and that in our case should be
Rafa so the statement that you used to
do that is called pop and with pop you
don't have to mention the element that
you want to remove it automatically pops
out the last element in the list so it
just accepts one argument that is the
name of your array and that in our case
is players and on line number 14 I have
a print statement to see the fourth
version of this players variable just to
confirm whether this statement has
worked and then finally let's say you
want to remove an element from the
beginning of an array right the command
or the statement for that is called
shift it automatically
ships out the first element from your
list so to confirm whether this has
worked or not I have another print
statement on line number 17 and this is
going to print the final version of the
players list which should also be the
original version by the way so let me
make sure this is saved and I'll run the
script by pressing f5 so there we go we
see that the player set one has Roger
and Andy then we use the post statement
to add refer to the list so we have
Roger Andy and Rafa now and then in
version 3 we added Novak at the
beginning so we have Novak Roger Andy
and Rafa and then we used the pop
statement to pop Rafa out so we are left
with Novak Roger a 90 and then finally
we use the shift statement to shift
Novak out of the list and we are left
with the original version which had
Roger and Andy so that's it for this
tutorial I hope you guys had fun
watching this one you may subscribe to
my channel if you haven't already I'm
going to see you in the next tutorial
till then take care