System.out.print the winning line only

Issue

I have a java lottery game assignment and where I am running a while loop to prevent duplication of numbers in the result. I am getting a list of numbers with no duplicates, however the System.out.print is returning all lines until I get the final one with no duplicates. Is there a way to only print the final "winning" line?

Code below

while (numCount<=9) {
  int randNumber = rand.nextInt(99)+1;
  if (results[0] == randNumber || results[1] == randNumber || results[2] == randNumber || results[3] == randNumber ||
        results[4] == randNumber || results[5] == randNumber || results[6] == randNumber || results[7] == randNumber 
        || results[8] == randNumber || results[9] == randNumber) {
    
  } else {
    Array.setInt(results, numCount, randNumber);
    numCount++;
  }
    
  System.out.print("The Lottery Numbers are: ");
    
  for (int i=0; i<10; i++)
      //add a 0 in front of the number is it's less that 10
    if (results[i] <10) {
      System.out.print("0"+results[i]+" ");
    }
}

Solution

You can do this simpler, relying on the fact that a Set does not have duplicate objects in it.

public static void main(String[] args) {
    Random rand = new Random();
    Set<Integer> winningNumbers = new HashSet<>();

    while (winningNumbers.size() < 9) {
        int randNumber = rand.nextInt(99) + 1;
        winningNumbers.add(randNumber);
    }

    System.out.print("The Lottery Numbers are: ");
    for (Integer number : winningNumbers) {
        //add a 0 in front of the number is it's less that 10
        if (number < 10) {
            System.out.print("0" + number + " ");
        } else {
            System.out.print(number + " ");
        }
    }
}

You can even simplify the way you are printing the numbers, relying on printf() and %02d, which means that 0 paddings are used being the maximum width of the printed numbers 2:

public static void main(String[] args) {
    Random rand = new Random();
    Set<Integer> winningNumbers = new HashSet<>();

    while (winningNumbers.size() < 9) {
        int randNumber = rand.nextInt(99) + 1;
        winningNumbers.add(randNumber);
    }

    System.out.print("The Lottery Numbers are: ");
    System.out.printf("%02d %02d %02d %02d %02d %02d %02d %02d %02d", winningNumbers.toArray());
}

---

In your code, just move the line System.out.print("The Lottery Numbers are: "); to before the while loop and the loop for (int i=0; i<10; i++) to after the while loop as follows:

System.out.print("The Lottery Numbers are: ");
while (numCount<=9) {
    int randNumber = rand.nextInt(99)+1;
    if (results[0] == randNumber || results[1] == randNumber || results[2] == randNumber || results[3] == randNumber ||
            results[4] == randNumber || results[5] == randNumber || results[6] == randNumber || results[7] == randNumber
            || results[8] == randNumber || results[9] == randNumber) {
        
    } else {
        Array.setInt(results, numCount, randNumber);
        numCount++;
    }
}

for (int i=0; i<10; i++)
    //add a 0 in front of the number is it's less that 10
    if (results[i] <10) {
        System.out.print("0"+results[i]+" ");
    }

Answered By - João Dias