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Coding

Greenhorn
Posts: 17
I am trying to write a program that requires the program to select six different numbers from integers 1 to 49 and then generate five sets of entries.
so far I have :
public class Lottery{
public static void main(String [] args)
{

int number =0;
number = 1 +(int)(49 * Math.random());
System.out.println(number);

}
}
how do you select 6 random numbers from 1 to 49?
I really don't know where to go from here. Any help would be appreciated.

Ranch Hand
Posts: 219
Becky,
Why not just generate all 6 numbers like you have done with "number" in your code?
int num1 = 1 + (int)( 49 * Math.random() );
int num2 = 1 + (int)( 49 * Math.random() );
int num3 = 1 + (int)( 49 * Math.random() );
int num4 = 1 + (int)( 49 * Math.random() );
int num5 = 1 + (int)( 49 * Math.random() );
int num6 = 1 + (int)( 49 * Math.random() );
And you could generate the entries the same way...(if by entries you mean what I think you mean)
~Ryan

Ranch Hand
Posts: 63
Also, Don't forget to put a method in to check and see if the number has been used already. I would suggest putting all of the chosen numbers into an array, and then check the new number against the existing array elements. Something along the lines of...

should be a start.
Pat B.

Ranch Hand
Posts: 4702
9
If the numbers have to be unique I would do the same as Pat suggested.

 It is sorta covered in the JavaRanch Style Guide.