Question

In java:

write a lottery program that picks 4 random numbers between 1-9 and print the number. If the number is a duplicate, then run it again until there are no duplicates.

Answer 1

import java.util.Random;
public class Lottery {
  public static void main(String[] args) {
    Random random = new Random();
    int arr[] = new int[4];
    int k = 0, num, j;
    for(int i = 0;i<4;){
      num = random.nextInt(9)+1;
      for(j = 0;j<k;j++){
        if(num == arr[j]){
          break;
        }
      }
      if(j == k){
        arr[k++] = num;
        i++;
      }
    }

    for(int i = 0;i<4;i++){
      System.out.println(arr[i]);
    }
  }
}