koobas.hobune.stream
Non-repeating random number generator crashing unity
Hi everyone,
I know there are some threads about non-repeating random number generators, but I wanted to write my own. However, my code keeps crashing Unity and I cannot figure out why.
private int[] used_list = new int[10];
public int trial = 1;
private int intRand;
private bool success_flag = false;
private int position;
private GameController gameController;
for (int i = 1; i < 5; i++) {
while (success_flag == false)
{
intRand = Random.Range(1,4);
success_flag = true;
for (int j = 1; j < trial; j++)
{
if (intRand == used_list[j]) { success_flag = false; }
}
}
used_list[trial] = intRand;
success_flag = false;
if (used_list [trial] == 1) {
position = 0;
gameController.position = "AB";
} else if (used_list [trial] == 2) {
position = 90;
gameController.position = "BC";
} else if (used_list [trial] == 3) {
position = 180;
gameController.position = "CD";
} else if (used_list [trial] == 4) {
position = -90;
gameController.position = "AD";
}
Debug.Log ("The wall " + gameController.position);
Debug.Log ("The position " + position);
Debug.Log ("Should be a random number " + used_list[trial]);
Debug.Log("The trial " + trial);
trial += 1;
}
So what this script does is pick a random number and check if the number has already been used in the array. If it has, the success_flag is set to false and the loop starts again and picks a new random number. It does this until a number that hasn't been used is picked. That number then gets saved in position "trial" for the array used_list.
The current random number should then be shown by calling used_list[trial]. Unfortunately, this crashes the program. Anyone know why?
Nope, my scene just doesn't run when I hit play and then I need to use Ctrl+alt+Delete to close unity. If I get rid of the trial += 1 part at the end, it runs but then repeats numbers.
Sounds like an infinite loop. I cannot see where... yet...
How to fix is script and how to you finish loop answer me please
Random.Range with int, the second parameter is exclusive, so it never gives 4. use Random.Range(1,5), and you won't get an infinite loop
This is of course a valid answer, but if you plan to use this code to generate more random numbers, e.g. in range 1 - 100, then you need to change it. Currently, you're wasting a small number of Random calls, but for 1 - 100 range, you'll waste about 10000 of those. It could have a real impact on performance.
to ArkaneX, this is not an optimized algorithm, you'll need to change it if you want a lot of iterations. The time this algorithm will take will grow exponentially.
