Trying to generate second random number less than first random number-CodePudding

Ive been trying to generate a second random number less than my first random number in every scenario, but the code keeps breaking or sometimes returning null

     
    Random randN = new Random();
    
     int firstNumbereasy; //declaring variables  for easy mode
         int secondNumbereasy;
    
    firstNumbereasy = randN.nextInt(11); // 
    secondNumbereasy= randN.nextInt(firstNumbereasy-1);

CodePudding user response：

You can do it by running the following:

firstNumbereasy = randN.nextInt(MAX_RANDOM_NUM_NUMBER)   2;
secondNumbereasy= randN.nextInt(firstNumbereasy - 1);

Note that the 1st number can never by 0 as otherwise you might get an exception while trying to generate the 2nd number, and that's why you always add 1 to the result...

CodePudding user response：

The answer is in the Random.nextInt(bound) docs.

To cite:

Returns a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive)

And

bound - the upper bound (exclusive). Must be positive.

Parameter bound must be strictly greater than 0. If your first nextInt() call generaters 0 or 1, the next bound parameter will be invalid value (0 or -1) and this results in exception.