rand() existing variables?

This is a discussion on rand() existing variables? within the C++ Programming forums, part of the General Programming Boards category; is it not possible to randomize already existing variables? char a="hi"; char b="I am"; char c="new to this"; ?...

  1. #1
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    rand() existing variables?

    is it not possible to randomize already existing variables?

    char a="hi";
    char b="I am";
    char c="new to this";

    ?

  2. #2
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    Your question doesn't really make that much sense.
    What is the actual problem you are trying to solve?

    [I can think of at least three different things that you MAY mean - but I'm not going to post any of them, as I'd probably get it wrong anyways].

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    I got X number of different variables...all decleared with Char.

    what I want is to "cout << variablex"

    so each time the program starts it will send 1 random of the variables to the screen, then shut down
    .

    sry if that didn`t make much sense

  4. #4
    and the hat of wrongness Salem's Avatar
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    Declare an array of them.
    Then generate a random subscript.
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    so you said you have x char variables, and each time the program runs, you want one of the x char variables to print, and then exit?
    Code:
    int main()
    {
        char myChars[] = { 'a', 'b', 'c', 'd' };
        // seed random number generator
        int random = // call function to generate random number from 0 to 3 inclusive
    
        cout << myChars[random] << endl;
    }
    is this logic something that your looking for? again, to me this seems like what you are asking

  6. #6
    C++まいる!Cをこわせ! Elysia's Avatar
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    Also use const char* for string constants or (const) std::string.
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    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

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    Quote Originally Posted by ignotus View Post
    I got X number of different variables...all decleared with Char.

    what I want is to "cout << variablex"

    so each time the program starts it will send 1 random of the variables to the screen, then shut down
    .

    sry if that didn`t make much sense
    You can't do THAT, but as suggested elsewhere, you can use an array and a random index to achieve the effect you want. But what you suggest involves runtime decisions on which variable to use, and the C or C++ languages do not support that.

    Edit: And of course, if you are REALLY desperate to not create an array of your variables, you could make an array of pointers to the original variables, e.g.
    Code:
    char *a = "Hi";
    char *b = "Hello";
    char *c = "'Morning";
    char **arr[] = { a, b, c };
    ...
    --
    Mats
    Last edited by matsp; 01-01-2009 at 01:01 PM.
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  8. #8
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    thanx for the replies.
    I did load them into a array and then randomized them.

    worked wonders

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