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Hey everyone, welcome to Simplified by
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Singum. Welcome back to our Python for
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beginners series. Today's exercise is
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super exciting because we are going to
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print the first n even numbers. If you
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have just started coding, this is a
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perfect way to understand loops and how
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Python can generate sequences of numbers
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And here is what our flowchart tells us.
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So first we ask the user to enter a
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number and let's call it n. And this
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number tells us how many even numbers we
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want. And we start counter at i = 2. And
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because 2 is the first even number and
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then we enter a loop and we print i and
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we increase the i by two. So we always
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get the next even number.
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It's like saying keep adding two numbers
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and printing the number until we have
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reached the count of the numbers that
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It's like for example user gave value
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six. So it will give you the values for
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the first six even numbers. That means
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it will add two six times and it will
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give you the first six even numbers. 2 +
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2 + 2 + 2 + 2 and + 2.
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Simple, right? Now, let's write the
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Python code to make it happen. Always
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Let's call it n. And we need this
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integer this time. Input.
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Enter the value of n.
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Okay. And you will print.
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So we'll create a variable called i and
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we'll give the initial value two. And
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we'll also create one more variable
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called count. And we also give it zero.
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And then also you will increment count
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count equal to count + 1.
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Let's break this down. So what's
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happening here? Here we are taking the
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user value n as input. So user will give
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you how many even numbers he or she
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want. And we are printing the first n
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even numbers like you gave me to get six
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even numbers. So this is what this print
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statement is for. And then we created
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two variables. One is i because two is
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the first even number. We gave the value
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two. And we gave the count value zero
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because this will keep track of how many
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numbers we have printed so far. And
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while count less than n, this loop keeps
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running until we have printed n numbers.
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Like for example, the n value is maybe
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four. Okay. And you and you will tell to
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the user that first four even numbers
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are something like that. And then you
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gave I value two, counter value zero.
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And now initially count value is zero
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and n value is four. Is 0 less than
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four? true then it will come here it
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will print two as output.
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Okay. And now the I value becomes
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initially it was two and now the I value
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becomes four because I = I I + 2 which
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is nothing but 2 + 2 is nothing but four
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and now the count value changes to 1.
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Initially it's zero and now it became 1.
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Now again the program jumps here. Is 1
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less than four? Yes. Now again you will
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print I which is nothing but four this
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time. So this will be four. And now
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again I value increments by two. And
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this time the I value will be six and
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count value incremented by one. And now
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the count value becomes two. And now
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again the program jumps here. Count
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value is two. Is two less than four?
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True. So it will print the i value which
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And again the i value increments by two
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and this time it becomes 8 and count
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value also will be incremented by one
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and this time it will be three. And
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again now the program jumps here is
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count less than three less than four
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true. And now again it will print i
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value. Now it will print the i value and
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the i value is 8. So it will print 8
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and again now I value will be plus equal
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to 2. So this time the i value will be
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and the count plus equal to 1
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and this time the count value becomes
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And is four less than four? Listen to
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me. Four less than four false. So it
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will come out of the loop and you will
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see these outputs 2 4 6 8. So it is
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printing the first four even numbers.
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maybe four. So the first four even
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numbers 2 4 6 8. But instead of getting
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in you know each output in one line I
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want all of them something like this.
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something like 2 4 6 8 and I want the
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output something like this. So how can I
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get that? So for that all you have to do
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So it will just print everything in the
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So it actually prints the current even
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number on the same line. That means the
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entire output will be in the same line.
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The first four even number is 2 4 6. You
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can also give comma here. You can give
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any digit that you want to end
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something like this. I feel this is
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easier. So that's why I gave this.
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So it is giving the first six even
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So this print so it actually prints the
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current even number on the same line and
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this will jump to the next even number
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and this increments for every loop and
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yeah that's it. A perfect combination of
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loops and arithmetic to generate numbers
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Awesome guys. You just learned how to
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use a while loop to generate sequences
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in Python. Loops like this save you from
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writing repetitive code and makes your
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program much smarter. And here is a
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challenge for you. Try modifying this
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program to print first n odd numbers
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instead. And also comment below if you
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can do it. And hey, if you're loving
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these step-by-step exercises, make sure
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to like, subscribe, and hit the bell
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icon so you don't miss any future Python
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lessons. Remember, every line of code
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you write makes you a stronger and more
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confident programmer. Keep coding, keep
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experimenting, and I'll see you in the
