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High this is getting at the heart once again welcome to the next video of this collection.

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More to now.

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In the previous two videos we talked about the Adye and list in girdling.

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So in this video we will discuss about the maps in Garling.

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So inside the map the Village Code Vawter immutable map and murid table map.

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So first of all let's take the immutable map that supports only read only operation using that method

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of map of.

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So here inside the intelligent Id let me clean up my code.

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So what is actually a map now the map is actually their data structure.

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So this data structure contains the elements in the form of key value pair.

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So each value is specified is connected to a specific key that you will check out shortly.

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So what do we mean by this is to define a map.

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We need to use the VAT or value keyword.

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Let's see my map equals to map of.

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Now this map of the regions the immutable map.

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Now this map of keyword actually returns the immutable map that is it cannot be mortified later once

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defined and it has also the fixed size and it can support the read only operation that is you can only

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read the content of the map but cannot modify in future aspart your requirement.

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So to define a map you can simply use map of followed by their template.

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Now their template contains the key value before the key can be laid.

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And in either case.

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And the value can be a string.

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Right now this key can also be a good order.

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This can also be flawed.

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But anarchies I'm keeping it in.

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Right.

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And this value can also be and and any combination can be applicable here.

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As you would wish and flowed into string into God and Boullion and so on.

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But right now just use string right now since we have defined the end and string as a key value period.

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That is the key will be in.

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And the value will be string.

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So inside the constructor.

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So while initializing all the values we have to define the key value pair in a similar fashion that

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is let us define the key as to who going to.

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Let's see Yugi separated by a comma second element Nerk see 43 going to alert them and move on.

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And then the third element does define the key value appeared as let's say seven going to be.

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So here I have simply defined the key value.

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Here is the key as a first element and as a first element I have the value of Yugi and here the key

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is 2:56 value as Menuhin keys 7 and value as fee now make a note here that inside the map since they

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are present in a sequence.

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But the key need not to be in sequence that is.

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This too can be fought as well.

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Right.

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And therefore it is not necessary that it has to be a greater number.

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It can be any number it can be one as well.

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So there is no sequence of the key.

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You're going to define any interior value.

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So the form will only map to Yugi and 43 will only map to 1.

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And now since this my map is actually immutable in nature.

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So you cannot say put any other elements inside this that is once defined you can not mortify in future

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you can only print or the values using the print and in the statement or the for loop.

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Right.

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So it's for this let's just print out the elements inside the immutable map by using the key.

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So here I would simply define the key and then my map door keys.

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So my map darkeys will simply return all the keys.

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Is fluid 43 and 7 and stewarded inside the key variable.

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One by one.

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So here I will simply use large see my map of key.

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So my map of Kiev is simply the return the value associated with that key that is your game and Mohon

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and speed.

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And in the output console you will get all the outputs the output.

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So here we go to Yugi maneuver and Vajpeyi And now instead of my map of the key.

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You can also right let's see my map Dorte get the value are this key.

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So instead of my map key you can also use my map dord get the value Akki right.

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So both ways it will work.

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So here let me mortify my brain.

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And in the statement.

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So here element present at this key and here I am simply appending are the key and also the map dot

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gate key.

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So here I will use my map and are get are in sort of this.

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You can also use my map are the index of key.

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Right.

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So let us note in the chord.

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So here we get element agcy that is Axford we have Yugi at 43 I have Manoharan at 7.

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I have Vice B.

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Now in future suppose you want to mortify large c I am going to modify my map so far that you can do

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it because it is immutable in nature.

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So the Cartland provides the mutable map that is immutable collections.

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So inside of them you will map.

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You can simply use hash map hash map of mewled table map of.

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So let us try these things inserted there in Delage ID.

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So any sort of map or if you can simply use the hash map.

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So this hash map again if you are from Java background then you must be familiar with this hash map.

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It contains a value as a key value pair.

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Now redefine a hash map there just remove all these called from here.

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And on that site I would simply use my map Dorte and then simply pass the first pyramided aski.

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Let's see.

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Food coma UGI and similarly I will add my movement and watch be.

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So here I have simply added two more elements and here this hash map is actually mutable in nature.

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There it is we can perform the read and write operation Buddh and it has no fixed size.

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There it is.

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In future we can add more and more elements.

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As for our vish.

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And now to print out all the elements the code will be same as we have defined here.

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So as of now let us run the call and we get the same output in the output console.

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Right.

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Now suppose in future you want to replace this man than by let's see Moody.

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So later on what we'll do inside your code you will simply use my map dord.

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Let's see say replace method.

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Now simply define the key as 43 and then the new value to be inserted.

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Legacy Mordy.

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So whatever is present.

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So whatever value is associated with 43 key will be replaced by Moody.

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So this movement will be removed and it will be replaced by Moody.

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So let us note in the chord.

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So here we get Axford we have Yugi seven vice B and at 43 instead of Menuhin I have more D.

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And now instead of using the replace you can also use the method.

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Now insert the apartment.

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If you pass 43 and then the new value.

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Then again it will work like replacement.

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So at 43 it will simply insert moody and maneuver and will be forgotten.

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So let's see what happens.

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So in the output again we have an index of agcy of 43.

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We have the someone movement is on now at the end of this video.

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I would like to show you a few more things now instead of hash mathy You can also use a few more keywords

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such as table map of.

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And also you can use hash map off.

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Now all these three are actually representing a hash map.

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The only difference is that this new table map of actually returns of the hash map.

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Now since this is a big net of course.

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So as of now I do not want to talk more about this link.

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Hash map but just remember more or less all these three are seeing all these three are actually returning

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a hash map.

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So in this video we talked about the map off and also hash map hash map off and mutable map of.

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And also we learned the difference between the mutable map and immutable map.

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So in the next video we will check out Vawter immutable set and they will have said that has their own

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functions such as say golf and your table is set off and so on.

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Let's take out in the next video.

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Thank you.