一个随机数算法

 

 question:

suppose give a function Randomnized(1,N), it can generate from 1 to N random Integer number, pls use this function to accomplish a most effective program, it can generate 6 unduplicate nubmers.

answer:

publicclass RamdomNumber {

 

      publicstaticvoid main(String[] args) {

           

            int numbers[]=newint[50];

           

            //add values to numbers array

            for(int i=0;i<50 ;i++ )

            {

                  numbers[i] = i+1;

            }

 

            int[] luckyNumbers = newint[20];

           

            int i = 50;

 

           

            for(int j = 0; j < 20; j++)

            {

                  int index = (int)(Math.random()*(i-1));

                 

                  System.out.println(index);

                  System.out.println("*************");

                  luckyNumbers[j] = numbers[index];

                 

                  numbers[index] = numbers[numbers.length-j-1];

                 

                  i--;

            }

     

            //output the values

            for(int t = 0; t < 20 ; t++)

            {

                  System.out.println(luckyNumbers [t]);

            }

      }

 

}