Random number problem

[jongiambi]

Hi im writing a program to simulate a slot machine, where a user enteres a coin and has a 70% chance of winning (say 3 coins). Anyways, I have a class slotMachine with a public int random() function.

Here is the function:

int slotMachine::random()
{
    srand( time(NULL));

    randomNum = rand() % 7 + 1;  // from 1 to 7
    return randomNum; 
}

The function should generate a number between 1 and 7, if the user enters a number between this they win.
However, when I run the program and test to see what number the function prints it always prints 5. Is this because srand(time(NULL)) generates a long value, and when I try to convert it to an integer it only prints the first number of the geterated long type value? How can I fix this?

[jongiambi]

Alright I think I got it.

int slotMachine::random()
{
    srand((int)time(0));
    //srand ( time(NULL) );

    randomNum = rand() & 10 + 1;  // from 1 to 10
    return randomNum; 
}

Random number between 1 and 10 means 70% chance of winning.

[KaeLL]

the srand() must be putted into your main() function, so it can seed correctly..
there is no need to change nothing else.. just put it on main() and test it!

[Lucaci Andrew]

Try to get out the srand() part from that function. Srand() generates a seed for your rand() function, thus it should be put just 1 time in your program, most likely in your main function since it's the starting point of your program and it is called just 1 time. If you put it in your slot function, whenever you call that function the srand() will be called too, with the same parameter, thus generating the same random number.

[jongiambi]

Ahh of course. Got it. Thanks

[KaeLL]

Also, the new C++ Standart has another, and ( for my point of view ) better random number generator.
Check it out: Click Here
PS: It depends of availability, so, last time I checked, works on VS2012, but on GCC still a pseudo-random number generator!