java, excluding numbers?

[mikeE]

im still learning java and i want to make a random number generator that exludes zero (0).
i asked my teacher how to do it but she has no clue .... -_-
we're learning how to generate random numbers

import java.util.Random;

public class RandomNumbers
{
	public static void main(String [] args)
	{
	Random generator = new Random();

	for(int i = 1; i<=5; i++)
		{
			System.out.print(generator.nextInt(5) + " ");
		}
	}
}

i'm trying to make a card game in java ... and i know that cards don't have a 0 card =(


thx, any help will be appreciated

 

[ameoba]

if the RNG outputs numbers in the range [0,n] and you want [1,n], tell the RNG to give you numbers [0,n-1] and add 1.

 

[berky]

likewise, you can return a random number in any range you want by using that same logic

ie. random number between 10 and 20

print random(10) + 10;

ie. print random(max - min) + min;

of course that can vary slightly depeding if the random generator includes or excludes the value sent as the parameter

 

[BillLeeLee]

Well, since the Random class's nextInt(int n) method generates a number between 0 and n, you should just add 1 to the return value to get a value from 1 to n+1.

Random rng = new Random() //automatically seeded with a 48-bit number I think
System.out.println(rng.nextInt(12)+1); //prints some 'random' number between 1 and 12.

Is that what you were looking for?

As a note, nextInt(int n) generates a number from (0, n] (0 inclusive to n exclusive, I forget whether I used the correct bracket for each though). This means that if you put in 12, it'd only generate a number between 0 - 11. Adding 1 gets you a number from (1, 12).

 

[lomn75]

As a note, nextInt(int n) generates a number from (0, n] (0 inclusive to n exclusive, I forget whether I used the correct bracket for each though). This means that if you put in 12, it'd only generate a number between 0 - 11. Adding 1 gets you a number from (1, 12).

That would be [0, 12).

Nothing more to add otherwise, just figured I'd address this point real quick.

 

[BillLeeLee]

Thanks for the correction, lomn.