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Hi, everyone.

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So in this video, what we will do, we will implement the remove function and get value function.

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So now first let's discuss the remove function.

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So you are given a key and you want to remove that key.

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So what is the procedure?

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So procedure is very simple.

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First of all, this key will pass through a hash function.

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So get index function, get a good index function and that will return me the bucket index and what

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we'll do.

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We will go to that index.

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So this is our bucket, Buckethead.

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Now we will reach this index, so this index, what we have, we have a long list.

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Now, suppose you want to delete ABC, the key given is ABC.

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So you want to delete ABC.

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So after reading this index, what will do?

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We will reach the pointer then, let's say.

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My ABC is present here.

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So what we have to do, we will iterate over this link list and we will compare the keys.

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So this ABC, we have found the key, which is to be deleted.

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So after finding out the key that we have to delete what we will do.

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So we have to delete this node.

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So for deleting this node, we know we have to take a previous pointer.

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So this is previous pointer and this is current pointer.

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And we will do something like this.

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So basically, we will do the next of previous is actually the next of current.

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So we have to do something like this.

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So this link will make.

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So now let's write the code for the more function.

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So this is my remote function, it is taking as input, so we will copy some gold.

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So first of all, we have to do we have to find the bucket index.

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Then Waterloo, so we need the head of the linked list.

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So after finding out the head of the linked list, we need one more pointer, previous pointer so that

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we can delete.

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So we need previous pointer and this previous point is initialing than simple.

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Then what we have to do, we have to iterate over the linked list, so now let us say teetotaling list.

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So, Heracles.

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Next offered, and we also have to update our previous point.

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So what we will do, we will first rate privacy equals head and then our head will move ahead.

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Simple.

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So inside this, when we are dealing with an analyst, what we have to do, so we have to check.

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So if headachy.

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Is it close to the key that we have to remove?

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Then what we will do so at this point, so this is my head instead of current time using the variable

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head.

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So if Hedgie, which is ABC, is it close to the give?

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And then we have to delete this.

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And so basically we have to write this statement, this line.

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So what will do so previous.

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Euronext is actually.

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Head next.

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Simple, but there is a problem with this and it is the problem.

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So problem is very simple.

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So let's see.

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So this is your budgetary.

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This is your budget index, BMI is your baggage index, and then you have the list.

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Now, suppose you want to delete the ABC and ABC is present at the head only, so this is the head and

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ABC's president at the head only then they have to do so.

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We have to delete this node and we will update.

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This one, so at this point, what is the coalition so devious is actually Linell previs is actually.

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So if previous horsnell what we have to do, so we have to update our Buchard index.

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So we will we will link this node and this will be our new link, so let's do this so we can we cannot

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write like this.

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So we have a condition.

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So if previous is null, so that means I have to delete the hardpoint, but only the first node, so

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for the leading the first node, what do we have to update our baggage index?

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So what will happen next?

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So it will be.

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Next offered.

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Simple.

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And in the part.

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We can do something like this.

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So if previous Horsnell.

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If privacy, then you have to update your bucket index, in the other case, you can do like this simple.

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Now, what we have to do, so we have to remove so far removing.

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So what do we have here, so I have.

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So this is my previous pointed.

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And this is my head, basically the current pointer, and this is the next node, so initially this

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is a situation now of writing the code.

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This is the situation.

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So what I have to do, I have to delete this node.

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So I will write, delete my current node.

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But if you will write like this, if you will write delete, then what will happen?

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So this whole linked list.

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So this whole list will get destroyed because of this link.

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Because of this link and and we have written our district cursive, so our district cursive.

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So what will happen, if you will write simple like this, delete current, then this complete link

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list will get destroyed.

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So what we have to do, so we have to make we have to remove this pointer.

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So for removing this point, what we will do so we will first write current error.

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Next is null.

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So first, we will isolate this node.

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It will point towards.

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No, this note is isolated and then we can delete this old simple, so let's do this.

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So we have to do we have to.

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Believed had actually been to Canada directly because if they had, then the rest of the English, which

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is present in front of it, will get destroyed because our delete function, our district is because

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of.

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So first you have to isolate that node.

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And what is the way to isolating that node will make the next point only.

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Now, this is correct, but if we will see the return, the function is.

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So basically first we have to store the value before deleting.

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So before deleting what we will do, we will store our value.

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And what is the value?

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So value is held at a value.

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Simple, now, one more thing.

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OK, so we have to return also, so delete and then you will return your values or return value.

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So I'm starting I am returning the saved value.

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Now, one more thing, since you are deleting a..

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What they have to do, you have to do minus minus simple.

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Now everything seems fine, but what if.

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I reach the end of the loop.

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So what if I reach at one zero two, so that means the given guy is not present.

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So if the giving is not present in the list, but we have to write down something, we have to retain

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value.

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So let's return a default value and let's say I am returning zero.

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So zero is basically the default value.

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So zero signifies here that the giving is not present.

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So if the value is integer, I'm going to return zero and if B is a pointer, then zero signifies null.

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I'm returning to return zero means the giving is not present.

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So this is the computer called.

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So in this remote function, we have to handle some cases, for example, first we have to check if.

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That means you have to delete the first, not only you have to delete this first.

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And not only.

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So that's why you did something like this.

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OK, so that's why you have the right bucket buckets of bucket indexes next of it, so next of this

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is head.

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Again, so when you're deleting the head, so first you have to make the head next channel so that the

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rest of the list present in front of it do not get deleted.

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So if you like deleted, then what will happen?

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So our function is our district, basically.

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So the rest of the list presented in front of it will also get destroyed.

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So that's why I had that on external so that we can isolate that node.

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But before deleting that note, I have to store the value because I have to return the value.

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So I'm returning the value.

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And we also have to do count minus minus and if we are not able to find the key.

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So if the key is not present in this linked list, then I am returning zero.

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So this is the remove function.

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Now let's also write the search function, basically the get value function.

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So there get value.

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OK, so this is the great value function.

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So again, we will copy the same code.

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So we just have to find a value.

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So for finding the value.

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Again, so given a key ABC, you have to find the value for ABC.

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Again, we have this key will pass through the hash function, basically get back index function.

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It will it will return the bucket index.

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I will go to that index in the area in my bucket.

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Very.

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And in this market index, what do we have, I have a long list so far finding out the value for the

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given key.

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What I will do, I will iterate over this linked list.

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So suppose ABC's present here and I will just hold the value the title.

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So I will compare ABC.

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But this ABC, if you're able to find out the key you will return to and if you read the complete link

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list, but you are not able to find out the given key.

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So that means the given key is not present and then you can return a default value.

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Simple.

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So let us also find out they had.

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Now, what you have to do, we have to it the linked list to find out the key.

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So while it is not a questionable.

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So how ridiculous next of Ed.

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Simple and you have to write if condition here.

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So if hedgie.

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Is it goes to the given guy, so that means.

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You find out you found the Gunji and now what we have to do, so basically you have to return the value.

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So we just have to return the value.

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We do not have to do anything.

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So you can directly return.

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Head of.

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Simple, now, if you will reach if you will come out of the loop, it will come out this way loop.

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So that means if you will come out this way loop, that means the given key is not present in my map.

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So if the given key is not present, so I can return a default value and let's say zero is the default

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value.

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So return zero means the given keys not present.

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So this is the computer get value function, so get value function, this very simple, this function

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is a little bit tougher, then get value function to this function is a little bit less function, a

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little bit more complex, then get value function.

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Now, in the next video, we will discuss their time, complexity of our hash map I will see in the

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next one by.