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java - Dividing a number into smaller random ints

So what i need is basically described in the subject.

Like if i would put in number 12 and amount of parts it should devide into, i would like it to return something like (with 4 parts) 8, 2, 1, 1. But not doubles because i need the values as int.
I had found one answer earlier but it only worked using doubles. not ints.
(this is the one i found)

public double[] divideUniformlyRandomly(double number, int part) {
    double uniformRandoms[] = new double[part];
    Random random = new Random();
    double mean = number / part;
    double sum = 0.0;
    for (int i=0; i<part / 2; i++) {
        uniformRandoms[i] = random.nextDouble() * mean;
        uniformRandoms[part - i - 1] = mean + random.nextDouble() * mean;
        sum += uniformRandoms[i] + uniformRandoms[part - i -1];
    }
    uniformRandoms[(int)Math.ceil(part/2)] = uniformRandoms[(int)Math.ceil(part/2)] + number - sum;
    return uniformRandoms;

I had tried changing this code to work using Ints by doing this:

public int[] divide(int number) {
    int part = getDivider(number);
    int uniformRandoms[] = new int[part];
    Random random = new Random();
    int mean = number / part;
    int sum = 0;
    for (int i=0; i<part / 2; i++) {
        uniformRandoms[i] = random.nextInt() * mean;
        uniformRandoms[part - i - 1] = mean + random.nextInt() * mean;
        sum += uniformRandoms[i] + uniformRandoms[part - i -1];
    }
    uniformRandoms[(int)Math.round(part/2)] = uniformRandoms[(int)Math.round(part/2)] + number - sum;
    for(int i : uniformRandoms)
        System.out.println(i);
    return uniformRandoms;
}

But when running that using number: 512 and using 10 parts (getDivider() will return 10) itll output this:

-1058809647, -2102647561, 469849949, 1627965716, -290084223, -33347991

And alot more of this kind of numbers.

Thanks.

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1 Answer

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Assuming every term should at least be 1.

public int[] divide(int number, int parts) {
    int[] randoms = new int[parts];
    Arrays.fill(randoms, 1); // At least one
    int remainder = number - parts;
    Random random = new Random();
    for (int i = 0; i < parts - 1 && remainder > 0; ++i) {
        int diff = random.nextInt(remainder);
        randoms[i] += diff;
        remainder -= diff;
   }
   randoms[parts - 1] += remainder;
   Arrays.sort(randowms);

   // Reverse (for getting a descending array):
   for (int i = 0, j = parts - 1; i < j; ++i, --j) {h
       int temp = randoms[i];
       randoms[i] = randoms[j];
       randoms[j] = temp;
   }
   return randoms;
}

This is not uniformly distributed. For that one could iterate till remainder becomes 0, everytime randomly picking an index to increase. Or so. Have fun.

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