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Hi everyone!

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So we have successfully coded the all nodes value remove function where a value is given, and in the

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doubly linked list, all the nodes with that particular value are removed.

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Now let's say this is the doubly linked list which is given to us, and let's say the value is given

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as two.

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So the value is two.

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So we need to remove these two right.

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So what's happening in this code.

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Let's quickly walk through it.

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Initially we have Cur is set to the head right.

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So this is the head.

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So cur is pointing to the head.

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Now we loop through the doubly linked list using the while loop while cur.

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So it will continue till cur comes to null because null is falsey.

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So when cur becomes equal to null and when we do this check, we will come out of this loop.

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Now over here we set temp is equal to cur.

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So temp is also set to cur over here.

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And then we move cur to the next value like cur is equal to cur dot next.

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So we move it over here.

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Now temp is pointing to one and cur is pointing to two.

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Right now we check whether the value of temp is equal to the given value, which is equal to two.

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Now we see it's not equal, right?

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So what do we do.

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We don't do this part right.

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And we come over here and we see cur is still truth.

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It's truthy right.

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So what do we do.

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We again set temp is equal to cur.

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So we move.

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This temp is mood.

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So temp is equal to cur.

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And again cur is set to cur dot next.

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So cur is moved.

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And now we again check whether the value in temp is equal to the given value.

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And in this case the value was two.

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And over here also we have two.

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So yes we call the remove function this dot remove temp.

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And this node over here is removed right.

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And there is no problem.

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We are not losing any data because this is stored right.

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We have the next we have whatever is next it's there.

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So when we remove this these two are connected together.

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Right.

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And cur now is over here.

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Now temp.

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Temp is now this node right at this point temp is this node.

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And that's pointing to null.

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And this is also pointing to null.

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So that's why we need temp right.

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If we did not have temp and if we just removed cur this would be cur and we would not be able to go

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further.

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Right.

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Because both of these are the next and previous of this node which is removed, which is removed using

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the function are now pointing to null.

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So that's why we have set car to car dot next.

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So that's not a problem.

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So we have removed this and again we come over here.

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Car is now still truthy.

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So we come inside and temp is set to cur.

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So temp is now set to cur again.

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And now cur is set to cur dot next.

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So we move cur again and we check whether the value is the same.

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So this is three and the given value was two.

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So these are not the same.

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So we don't go inside here.

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And again we come over here and cur is still truthy because it's pointing to a node.

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And we move temp.

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And again we move cur to car dot next over here.

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Right.

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So that's what we do over here.

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And then we check the value is the same we see.

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So we come inside and we remove this node.

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And then when we come over here we come out of the loop.

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Because at this point cur is pointing to null.

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And this is evaluating to false.

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And we come out and we have our solution.

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Right.

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One is now pointing to three.

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And it's also pointing back.

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And then these two are pointing to null which is the solution that we wanted.

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And we have seen that this runs in constant space because we are not using any additional space.

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But this requires O of n time because we need to traverse the given doubly linked list once.