Nested Loops Explained (step by step)

Transcript

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every time your outer loop runs every

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time

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a slice of that execution happens you

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are going to do

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the entirety of your inner loop now

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i know it's kind of hard to understand

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without visualizing it so i made the

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slide to basically

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step through the process of executing a

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nested for loop

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so let's actually get started here so we

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have

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this outer loop which has a variable i

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and

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this i is going to be initialized to

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zero so we initialize i to 0

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then we're going to begin this loop and

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it's going to immediately begin

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the inner loop which is going to be for

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j loop so it's going to have a variable

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j j is going to be initialized to zero

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then we are going to print out j which

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is going to be 0 the first time we run

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through this

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then it's going to increment j by 1

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because

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in this for loop at the end we see j is

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going to be increment incremented by 1

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at the end

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i hope that you understand how for loops

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works i'm not really gonna explain that

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process

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so then we go back up and we are gonna

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do the comparison

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between j and two so if j is less than

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two

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it's fine because j is equal to one we

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are going to print j

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then we're gonna increment j by one

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again

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then we are gonna go back up here we're

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gonna check is j less than two

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obviously j is equal to two now so it's

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not less than two

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so we are gonna go to the end of our

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outer loop

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when we do that we are increasing i by

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one

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then we go back up to our outer loop

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and we are going to check is i less than

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two

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because it is we are going to step back

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into

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our execution and we are going to

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execute the inner loop

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and this time we are going to initialize

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j to zero again

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because we initialize the j to zero the

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first time we run through this

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it's going to be equal to zero then we

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increment j by one

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and then we check if j is less than two

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again

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and then we print j then we increment j

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by one then we go back up and we check

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is j

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less than two well j is not less than

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two j is equal to two and because of

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that

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we are going to go to the end of our

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outer loop

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and we are gonna increment i by one now

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is i

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less than 2 no i is equal to 2 now

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and because of that both loops have

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finished

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once both loops have finished that is

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the end of our nested loop

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you