Original subtitles

0 So we had a script that checks if A is greater than 3 and prints out these operations. 1

If that is true no let me go ahead and use a more real world example. Let's create a variable here called 2

user name and give it a value of an empty string. 3

And here lets check if username is different than the real user name which let's suppose it's py py. 4

Now while that is true we want to ask the user 5

to enter a username. 6

So let's see what's going to happen. 7

Enter user name. 8

We got the prompts here by the input function py. 9

Note we get enter user name again. Pyp maybe, no. Pypy. 10

And so this time we don't get a prompt anymore. 11

The execution of the program ends. 12

So let me explain what's happened here. 13

We declared the empty string to variable user name and then here we check if the value of the username 14

variable is different than pypy. 15

In this case it's different because this is an empty string and this is pypy. 16

Therefore the first iteration will occur which is this one here. 17

So in the first iteration we are asking the user to enter some inputs. 18

This is what happens here in the first iteration. 19

So enter user name was prompted and we entered pi. 20

So pi now is the string that would the assigned to user name and the loop goes through the second iteration. 21

So while the user name is different than pypy which is true in this case because user name for now 22

it's py, the string py, so py is different than pypy, therefore go ahead and execute the body of the while 23

loop again which is this one here. 24

So ask one more time for the user name from the user. 25

So user name the user enters pyp 26

this time, the loop goes through the head through the beginning again and it checks if pyp is different 27

than pypy, that's true, get the user name again. 28

In this case we got pypy, so user name is pypy now. The loop goes again while the user name is different 29

than pypy. 30

In this case that is not true because in this case the user name is equal to pypy, so pypy is different 31

than pypy. 32

No, that's false. 33

So the third iteration this will be equal to false, and that is when the loop ends. 34

So for loops end when their container is exhausted. 35

And while loops ends when the condition is false.