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This is the solution of the three small
exercises I gave you in the previous video.

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So let's start with the first one.

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We have to ask for the name and the age
of a user and print the info on the screen.

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So I'm going to create
a variable, user name is

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equal to input and then
let's print a message.

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What is your name?

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Click by the space like this, press enter.
So what is your name? Let's say Bob.

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Okay, so now Bob is
inside the username variable.

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I'm going to say user
age is equal to input.

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How old are you?

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With another space and let's say 36.

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And now, well, we have
username and we have user age.

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So what we can do, we can print, for
example, hello username, you are user age.

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So let's do that. Hello.

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Okay, let's put a space and let's do plus.

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Okay, so we can concatenate
the different strings.

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User name plus and then,
for example, a comma,

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you are space and
another plus user age.

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And if you remember the
input here will give you a string.

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So as for now, the user
age is stored as a string,

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which is nice here because
that's what we need to do.

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We need to print a string.
So we don't need to cast this actually.

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So let's press enter and you
can see hello Bob, you are 36.

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Okay, that's it for the first exercise.

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Now the second exercise, you
need to ask the user for two integer

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numbers, add them and then
print the result on the screen.

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So because we need to add the two numbers,
I'm going to need to cast what we get here.

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So the string to an integer.

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So let's say A, we're
simply going to use A and B.

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Okay, for this A is equal to input.

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So let's say first number and
I'm going to put int like this.

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Okay, int input.

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First number, let's say five.

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And then B is equal to
int input second number.

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Okay, same thing.

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Let's give three.

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Okay, so now we have A and we
have B, which are both integer numbers.

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I can create another variable,
which is sum is equal to A plus B.

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Okay, now the sum is eight.

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And what I simply need
to do now is print the result.

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So to print the result in
one line, I'm going to do strA.

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So I'm going to cast A to a string, okay,
so we can concatenate different strings.

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And then I'm going to add plus between two
double quotes, okay, plus strB, like this,

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another plus, and then
equal and then plus str.

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So, and actually I'm going
to add some spaces here.

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To make it nicer.

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And we have five plus
three is equal to eight.

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Okay, and let's just see what happens
if I don't cast the integer to a string.

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You can see type error can
only concatenate str, not integers.

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Okay, so you can only
concatenate strings with strings.

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Okay, here this is an integer,
so I need to cast it again to string.

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Okay, so to make the operation,
you need to cast two integer.

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And then to print, you
need to cast two string.

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Okay, and for the third exercise, so we
need to create a list of four float numbers

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and then compute the
average and print this average.

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So I'm going to create the list first.

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So number list is equal to, and let's put
brackets and let's give some numbers, okay.

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Let's say 4.4, 5.5, 6.6, 7.7, okay.

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Like this.

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So number list, we have four values.

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I'm going to create a new
variable named average.

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So to compute the average, we
have to sum all the elements of the list

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and divide that by the
number of elements, okay.

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So to make the sum of all
elements, what I could do,

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I could do number list zero plus number
list one plus number list two, etc, etc.

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But that's really not convenient.

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So as I showed you before,
you can use the sum function.

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So sum number list, we'll just
sum all the elements in the list.

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And then you need to divide by
the number of elements in the list.

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And to know that, you
can use the len function,

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which is actually going to compute
the length of the number list.

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So length number list, I press enter.

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And now you have average 6.05.

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So that is the average of the list.

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Okay, so you can see with
Python, you can go quite fast.

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And just with a few lines of code,
you can compute the average of a list.

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All right.

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And that's the end of this first
section for the Python basics level one.