a random number creator--PLZ help !

This is a discussion on a random number creator--PLZ help ! within the C++ Programming forums, part of the General Programming Boards category; hi , i've been trying hard , but it doesn;t work : for a combat system ( to do dammage ...

  1. #1
    email for MystWind avatar MystWind's Avatar
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    Question a random number creator--PLZ help !

    hi , i've been trying hard , but it doesn;t work :

    for a combat system ( to do dammage etc ) i need random numbers at first using the rand(); comando works , but it will only give a random value one time and never changes it back.
    also I need to let it be influence by ( for example ) strenght level or so. how can I do this ? I really can't figure it out...

    thanks
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  2. #2
    It's full of stars adrianxw's Avatar
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    You need to seed your random number generator once at the start of your program. Subsequent calls to rand() will then give you different values. Look up the srand() function.
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    former member Brain Cell's Avatar
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    Quote Originally Posted by MistyWind
    for a combat system ( to do dammage etc ) i need random numbers at first using the rand(); comando works , but it will only give a random value one time and never changes it back.
    first you should know two things about 'rand()' :
    1. its a function not a 'command'.
    2. it generates pseudo-random numbers not random numbers.

    use srand() to initialize the random number generator with a seed number. To get a fairly random seed number , send function time() (defined in ctime , returns the number of seconds since 1970) with the argument NULL.

    this is how it would look like :
    Code:
    ...
    srand(time(0));
    int random_number = rand() % 10 /* makes sure the random number won't be bigger than 10 */
    cout << random_number << endl;
    ...
    you can get different numbers each time now.

    Quote Originally Posted by MistyWind
    also I need to let it be influence by ( for example ) strenght level or so. how can I do this ? I really can't figure it out...
    This can be done in many different ways. Just think for a while , i don't wanna spoil the fun
    Last edited by Brain Cell; 03-05-2005 at 08:16 AM.
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    Thumbs up

    thanks very much brain cell
    Last edited by MystWind; 03-05-2005 at 08:21 AM.
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  5. #5
    and the hat of wrongness Salem's Avatar
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    We can't do much unless you show us some code.

    Sounds to me like you're calling srand() a lot, if you seem to be getting the same number out of rand()
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  6. #6
    former member Brain Cell's Avatar
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    or he's not calling it at all. Show us your code so we don't start assuming things
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    email for MystWind avatar MystWind's Avatar
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    new one

    ok , I am going to write a new program on random numbers see if i get more troubles . well thank you very much !
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  8. #8
    email for MystWind avatar MystWind's Avatar
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    Talking wOOt , it works !

    yay this code works ! :

    Code:
    #include <iostream>
    
    using namespace std; // using standard libary //
    
    int main ( int argc , char** argv ) 
    
    { 
        srand(time(0));
    int random_number = rand() % 10 ;// not larger than 10 //
    cout << random_number << endl; //out puts it //
    cin.ignore(); // waits for an input and ignores it //
    }

    thank you 2 very much i'll post it when I've made it being influenced by strenght etc.

    ty !
    Last edited by MystWind; 03-05-2005 at 10:16 AM.
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