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Hey everyone, welcome back to the
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channel. If you're new here, I am your
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Lucky and I simplify programming for
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beginners like you. And in today's
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episode of module 3, we are going to
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work on conditions in Python. We are
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diving into something super important,
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which is the if, LF, and else decision
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structure. In the previous videos, we
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worked on if and else conditions. If you
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guys missed that episode, I'm going to
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keep that in the description. You can
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just go there and try to grab it. If you
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still have any doubts, you can comment
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down and you can start learning from
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here once you complete that episode. So,
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we are going to work on if, lif, and
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else structure. Now, don't worry if that
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sounds like a lot. We'll take it slow,
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break it down with real examples, and by
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the end of this video, I promise that it
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will click for you. And let's go.
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All right. So, we have already seen how
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if and else exactly works and how they
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help our code to make simple decisions,
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right? Like it could be choosing between
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two options. But what if you have more
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than two conditions to check? Let's say
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you're grading the students and based on
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marks and you want to assign grades A,
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C or maybe even an F. I don't want you
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to do that but yeah maybe it happens. So
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that is where we can use if L if else.
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So it lets you to check multiple
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conditions one after the other.
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Like for example, if this condition is
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true, then you can execute it. If this
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then the interpreter goes here and if it
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is true, then it will execute. If this
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is also false, so anything of them is
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not working out. So then it will go to
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the else block and it will just print
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whatever which is present in the else
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So let's I'm going to explain it once
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again. Let's understand what's happening
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here. So first Python checks condition
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one. If that's true, then it runs this
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block of code and skips the rest of
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them. If not, it checks condition two.
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If this is true, then it runs this
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Still the condition is false, then it
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goes it goes and check condition three.
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And finally, it will print this block.
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If none of those conditions are true,
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then it will go to else block and then
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it will print this line. It's pretty
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neat. Python goes step by step until
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something matches. If nothing matches,
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then it will execute this block.
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So let's bring this to life with an
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equal to 75. So this is the marks that a
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student got. Okay, just imagine if marks
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how do you give grades to students? So
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if marks is greater than or equal to 90
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then you will give a grade to that
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person right to that student.
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greater than or equal to 80
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then you are going to give that person
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my bad I'm typing something or the
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greater than or equal to 70?
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Then you'll just print
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What if the person got 60?
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He got a D. He or she got a D-grade. So
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what if the person is less than 60 which
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is none of these things? Then else
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So here's what we have got. So we have
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got marks variable which is 75 and we
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are we just assigned 75 grade
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and now so if the marks are 75 then
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Python will first check whether is it 90
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or more based on score. So it is not 90.
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So next it goes 80 or more. Still no
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75 and 80 is completely different. And
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now it goes here. Marks greater than or
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equal to 70. Yes. So it prints you got C
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So notice how it stops once a condition
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is met. That's the beauty of if l if
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Like think of it like a staircase. like
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Python walks down step by step until it
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finds the right one and it's like yes
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this is what I need and then it will
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leave the rest and it will just print
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the output just for you. If you want you
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can try it right away.
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So you got a C. So that's the beauty of
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it. So if you just skip 90
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So if it's 90 then it will check this
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line itself and then it will check this
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one and then it will just print it
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because it met the condition right
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that's why if you got 50
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I failed for sure see sorry you failed
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so it will go it will check whether 50
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and 90 are same No. Greater than 90? No.
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Greater than or equal to 80? No. Greater
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than or equal to 70? No. Greater than or
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equal to 60? No. Then it will simply
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print this else statement.
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So this is what if, l if and else
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So this is the example that we have
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worked on. So it will check the grade
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value top to bottom, step by step. If it
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meets the condition then it will just
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print and skips the rest of the part of
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So that's how if L if and else works. So
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I just want you to give some quick tips
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when using if L if and else. First tip
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is you can have as many L ifs as you
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want. It depends on the situation and
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depends on the conditions that you want
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to give. And the else block is optional
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but it will be super handy as a you know
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fall back like it is optional. You don't
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have to give this. If you don't give
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this what happens let's see.
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So it will just print nothing I guess.
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See it is not printing anything.
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See it is not printing anything. So
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but if you want to show something to the
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user that there's something wrong even
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in the data that the user given. So then
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you can use this else. I would suggest
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you to use else but it is not necessary
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to do so. Also keep that in mind that
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conditions are checked in order like
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from top to bottom. First this then this
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then this then this and this. If any one
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of its it met then obviously it will
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skip the rest of the code and it will
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print the output that you're expecting.
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So that's how if else works in Python. A
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powerful way to guide your program
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through multiple choices. In the next
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part we'll talk about nested if
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statements. That's when you know one
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condition is inside another. like it it
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is very useful for more complex logic.
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If this helped you to learn something
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new and interesting, give it a thumbs
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up. Subscribe for more beginner friendly
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Python lessons and also drop a comment.
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If you have any questions or want me to
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cover something specific, just comment
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that down. I will make video on that one
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as well. See you in the next one.
