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Not it's just because a very important topic called variable scope every variable has a scope which

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is basically the part of the program where the variable can be used and you get a compiler error if

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you try to use it outside off at school different kinds of variables have different scopes.

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That is variable is declared a class level have a different scope compared to variables declared in

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methods.

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Let's look at scope of class level variables variables declared at class level like instance are static

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where tables are considered global and they are accessible anywhere in the class only exception is that

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a class level variable cannot be assigned to another variable declared before.

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And here is an example.

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Here we are declaring three class level variables.

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I janky these variables are accessible anywhere in the class so as you can see they are also accessible

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in the method for you can also see that variable is declared.

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And in the very statement we're assigning it to variable g so that it's perfectly valid.

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But we also said that a class level variable cannot be assigned to another variable declared before

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it so here you can see that we are declaring variable k but we are assigning it to variable in the previous

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statement.

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So this is invalid as gay is not declared when we are doing this assignment.

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Background is that the same statement J called ok is valid within the method for.

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Even though we're able K is declared below method for that because by that method fools and broke all

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the class global variables are already initialized so it just doesn't matter.

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Vary your methods are written within the class so that's a large scope of class global variables.

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Next lips look at scope of local variables.

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We know that local variables are declared within methods or constructors are within block statements

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like statements a lookup table is accessible from the point of declaration.

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And if it's block hit block and be method constructor can go a statement here's an example.

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Here we have a method called fu the metalworkers for local variables b x z n y be them the metal parameter

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on your scope is the and dark matter.

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This scope of the x and z is also shown not the scope of media will X also includes the declarator site

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that is a part that declares variable z.

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That's the reason we're able to assign extasy but not that Z cannot be assigned to x when declaring

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X that is you cannot how N x is equal to Z commas equal to something that will not work CSCOPE would

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include any declaratives on the right plus the rest of the block next video right is part of an IF block

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.

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Unsoiled scope and so with that particular block.

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So as you can see accessing variable right outside of the if statement is invalid and it leads to compiler

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error and the other thing to note is that within the scope of a local variable you cannot really clear

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that same variable.

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For example you can see that a variable x is declared twice and the second declaration falls within

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the scope of Fosdike tradition and hence is invalid.

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Here is another example illustrating that within the scope of a local variable but you cannot really

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clear that same area.

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But here we are really getting variable x in the initialization part of the for statement and it is

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invalid in the earlier example really coloration was done in an IF statement.

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So what we just saw was that in local variable cannot be shadowed or hidden but we know that a local

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variable can hide a class level variable.

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We have seen that in the previous chapter so even though the class level variable scope is still valid

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.

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It can be done by a local variable.

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And here is an example.

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He had the class level variable x is hidden by the local variable x which is defined in the motard for

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.

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So when X is incremented it is basically incrementing the local variable x to access the class level

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variable x.

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We know that we need to use this reference Finally any mentors invoked from the current block will get

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a new scope that is very declared in the current block are not accessible in the invoke methods.

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Here is an example here and we have a method foo with a local variable x method isn't working method

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bar Witan method bar b cannot access the variable X declared in method foo so that's about it underscores

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the scope of both plus local variables and local variables I would say this just try out some of the

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examples myself for book Class level and local variables.

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Thank you