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Thread: Switch and break

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    Default Switch and break

    Hello! I just want to know if I understand the program correctly. The program looks like this;

    public class test{
    	static char bst = 'a';
    	static byte nr = 0;
     
    	public static void main(String[] args) {{
    		char bst = 'c';
    	}
     
    	switch(bst) {
    		case 'a': nr = 1;
    		case 'b': nr = 2;
    		case 'c': nr = 3;
    		case 'd': nr = 4;
     
    	}
    	Out.println("To "+bst + "belongs" +nr);
     
    	}
    }

    The output is "To a belongs 2", now the way I am interpreting this program is like this. We have this Class variable c that is initialzed as a and when we enter the switch after checking that it is a number 1 is assigned, but since there is no break we continue going down thus assigning number 2 where we exit the switch (via break). Am I understanding this correctly or ?

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    Default Re: Switch and break

    since there is no break we continue going down thus assigning number 2 where we exit the switch
    Where is the break after assigning the 2? I don't see it in the posted code.

    What happens when the code is compiled and executed?

    Using {{ makes for confusing code. Each { should be paired with its } below and in the same column in the source file.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Switch and break

    Oh wait I copied wrong, my bad and I know that {{ is bad but again it is a question from the test, and the output is: "To a belongs 2. Here is how the Code ACTUALLY looks like, sorry for the mistake earlier.

    [code=Java]
    public class test{
    static char bst = 'a';
    static byte nr = 0;

    public static void main(String[] args) {{
    char bst = 'c';
    }

    switch(bst) {
    case 'a': nr = 1;
    case 'b': nr = 2; break;
    case 'c': nr = 3;
    case 'd': nr = 4;

    }
    Out.println("To "+bst + "belongs" +nr);

    }
    }

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    Super Moderator Norm's Avatar
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    Default Re: Switch and break

    Yes that makes a difference.
    Now what is your question about the new code?

    Please edit your post and wrap your code with code tags:

    [code]
    **YOUR CODE GOES HERE**
    [/code]

    to get highlighting and preserve formatting.

    Why would a test use poor coding like {{?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Switch and break

    public class test{
    static char bst = 'a';
    static byte nr = 0;
     
    public static void main(String[] args) {{
    char bst = 'c';
    }
     
    switch(bst) {
    case 'a': nr = 1;
    case 'b': nr = 2; break;
    case 'c': nr = 3;
    case 'd': nr = 4;
     
    }
    Out.println("To "+bst + "belongs" +nr);
     
    }
    }

    Sorry for the mistake, here is the code, well it would use something like {{ to make it difficult, that is the European way.My question is,actually not a question but more of a comfirmation. When we enter the switch and case is a so we assing 1 to it, but since we dont break we just continue going assigning 2 and than break exists the switch. Because the output is "To a belongs 2" so I'd presume the missing break at the first line in the switch causes this.

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    Default Re: Switch and break

    That explanation sounds about right.
    Do you understand how the extra {}s around the char bst = 'c' statement creates a different scope than the code outside of the {}s?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Switch and break

    I think I do but I would mind a great explantion from you.

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    Default Re: Switch and break

    Ask google for explanations on scope. I'm sure there are some good ones out there.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Switch and break

    Will do thanks

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