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Random number is not reused

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Top Forums Programming Random number is not reused
# 8  
Old 11-30-2009
Quote:
Originally Posted by limmer
I tried deleting the RANDOM function and placing its contents inside main, then use a variable to feed the random number to the other functions. This works yet it defeats the whole purpose of using a function to generate a random number.
Why?
Quote:
This is for a website, so having to include this bunch of code inside every single webpage is kind of inefficient... That is why I wanted to use a single function.
An entire function call is more efficient than retrieving one variable? I think not.
Quote:
Is there no other way of achieving this by reusing the RANDOM function???
All these attempted solutions effectively do the same thing: Call rand() once, store the value, use it many times. Calling RANDOM() repeatedly is overhead on top of this, not "more efficient".
# 9  
Old 11-30-2009
Quote:
Originally Posted by limmer
I tried deleting the RANDOM function and placing its contents inside main, then use a variable to feed the random number to the other functions. This works yet it defeats the whole purpose of using a function to generate a random number.
Why does it have to be so since a function call is more expensive.
Quote:
Originally Posted by limmer
This is for a website, so having to include this bunch of code inside every single webpage is kind of inefficient... That is why I wanted to use a single function.

Is there no other way of achieving this by reusing the RANDOM function???
You can make the RANDOMNUMBER a static variable and avoid using caps for names...
Code:
int RANDOM(void)
{
    srand((unsigned int)time(NULL));

    static int RANDOMNUMBER = rand() % 99999; // create a random 5 digit number to be reused in other functions
    

    if (RANDOMNUMBER < 10000)
    {
        RANDOMNUMBER = RANDOMNUMBER + 10000; // correction because sometimes the number generated is 4 digits long
    }

    return RANDOMNUMBER;
}

# 10  
Old 11-30-2009
Quote:
Originally Posted by shamrock
You can make the RANDOMNUMBER a static variable
No you can't. Same error: initializer is not a constant. That only works in C++.
# 11  
Old 11-30-2009
Quote:
Originally Posted by Corona688
No you can't. Same error: initializer is not a constant. That only works in C++.
It works with C source as long as it is compiled with a C++ compiler.
# 12  
Old 11-30-2009
Which is something the OP obviously isn't using.
# 13  
Old 11-30-2009
Nothing stops the OP from using the freeware gcc-g++ compiler.
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