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Hello everybody and welcome back.

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And let us continue with our Python basics in this video we will cover the if loop.

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Now if lope is basically the most simple one I would say it basically just does the same as it says.

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So if something then do that and else do something else.

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So I will explain a little bit better.

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Don't worry.

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For now on let us open up our second program and let us see how we can actually use the if loop.

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So for that first of all let's open the interpreter.

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So just wrap your python and you will see this.

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Let's say we want to write the most simple if statement that we can write.

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So for example a equals three.

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This is simple to understand.

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We stored value of three to eight and then if a equals equals three then two dots.

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Now what this basically does the two equal sign checks.

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If the value of A is three.

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So if a really is three you can't really specify just one percent sign it will not work since 1 percent

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sine means that you are actually giving the value of three to a.

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You need to specify two percent.

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Pardon me.

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Two equal sign in order to check.

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Two in order to perform a check on a.

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If a really is three.

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So if a equals three we will do what we will actually print a is three.

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So we print a three and then we can add an or let's actually just leave it on this so we can see if

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a equals three print a is three.

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And as we can see it printed out a is three.

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But let's actually switch it up.

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So if a equals four print k is four.

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And if we press twice enter you can see it didn't print out anything since A is in four we specified

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eight eight to be three in our variable specification.

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So this is the most simple use of IF statement what you can do is basically make an if statement which

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will actually perform an action if a equals 4.

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And it will perform a different action if a isn't equal 4.

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So let me actually clear the screen so we can do that so all those dots system clear.

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And let's actually do the same thing.

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So a equals for example now five so we have a to be set to five.

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And right now we want to write our first if else statement.

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So if k equals equals five we hear habit and print.

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Then we want to print a is five.

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So this will only be printed out if a release five.

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And what you want to do right here else and then to dot sign and then enter once again tab print a isn't

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five a is some different number for example and press enter.

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And now if you press Enter second time pops you will see that we get a is five printed out.

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Since that is true a release is five.

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And it didn't even consider this statement since it got this one to be true.

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So if a equals five print a is five.

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And we got printed out a equal or a five.

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Now in the syntax syntax wise you need to make sure to add after if statement and also after L statement

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you need to add these two dots right here since it will not work.

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If you do not add that so make sure to double check that before you run your program and let's actually

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run our first or not first our second program has a narrow window so as our as our real program and

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not a program in interpreter or Python interpreter so unless we have our first program with this type

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Python 2 that by which is our second program as we remember our previous video we need to specify the

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path to Python so user been python.

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And after this we can actually run our code.

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So let's actually run a code that will check out if number is odd or even which is simple we will use

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and if else statement.

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So let's actually type your number one which is our or actually just name one number we need only one

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number.

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Let's use the input raw input function which will give our users of code are a choice to specify any

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number so enter any puts any number two dots closed.

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Double quotes then we closed two brackets right here and let's write an if Al statement right here.

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So what we want to do is if open up our brackets No.

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Module 2.

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Now this percent sign stands for module.

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Basically we use this in order to check out if our number is evil or it Your if it is odd if it has

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any remaining after the division.

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So this sign right here.

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Make sure to remember that this sign is module we will not be using it that much but it is still a good

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thing to know.

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And then equals equals zero.

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So if the Remain is zero then we need to specify that the number is even if it is not zero the number

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will be odd.

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So if we just type here two dots or remember to put these two dots right here enter and then tab it

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so always tab it in order to make sure that your code looks a little bit prettier.

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And in python I believe you cannot really write an if statement under the line in the same order you

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need to tab it in.

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So it knows.

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So the python knows that this belongs to the if statement.

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So right here we want to print.

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Number is even.

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And we want to specify here else which will happen in any other cases that the number isn't even which

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is the only case that the number is odd.

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So we want to print.

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Else print.

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Number is odd.

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And then we close the double quotes.

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So here we can see this is a simple program as well.

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So we perform the module and then we actually print if number is even or if number is odd.

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So let's control all this central control acts.

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Let's make the program to be executable with this command.

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So Python 2 the PI.

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And right now we can see it's negative mutable and let's run it.

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We hear we asked for a number we specify two it will say number is even if we just up here not Python.

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If we run once again specify three it will say number is odd which is correct.

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So that the simple use of R Python 3 scripts or PI pardon me of our Python 2 script with the if else

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statement.

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Now there is also another thing that you should know which also we will use is the L if statement which

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basically allows you to specify multiple statements and not just two so let's edit our code now let's

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actually write a different code.

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We will have three different statements so let's delete these two statements right here.

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We will leave the number to be here as a variable and we will leave the user to specify which number

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it will be.

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So let's see if no let's specify open brackets.

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If number equals equals to zero type here.

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Paw print number four given number is zero.

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And then we basically just go into the next statement.

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The next statement will be out if and then we need to specify an understatement right here.

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If so how if number is bigger than zero then again two dots print not give a number is positive.

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And then we call this double quotes and then the last statement will just be.

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Else.

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So in the other cases.

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So any other cases would be the cases where number is not bigger than zero.

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And the now and the one number is not equal to zero.

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So any other case would be print given number is negative.

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And then we close the double quotes so control over to save and control X to exit and you will see that

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our program is still executable even though we edited it so we can actually run it right away so Python

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to perhaps Python to enter any number.

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Let's add three it will say a given number is positive.

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If we run it again we give it minus two given number is negative.

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So since minus two is a negative number.

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And then once again zero even number is zero.

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So you can specify as many if statements as you want.

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So for example if you need to cover five different statements you would be specifying first in the if

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the next three in the Elif and the last one in our statement.

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Make sure to get to have the two dots at the end of each once and make sure to specify these statements

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in given brackets it is easier.

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You can also do it without them but it is a good practice to actually specify them in the brackets.

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So that would be about it for these four or pardon me for this if statement video will cover the fourth

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statement in the in the next video and I hope I see you there.

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My.