for (int i = 0; i < size; i++) {
    if (!allowRepetition && i > 0 && nums[i] == nums[i - 1] && !used[i - 1])
        continue;

    if (!used[i]) {
        used[i] = true;
        perm[index] = nums[i];
        generatePermutations(nums, used, perm, size, index + 1, allowRepetition);
        used[i] = false;
    }
}

for (int i = 0; i < size; i++)
    used[i] = false;

generatePermutations(nums, used, perm, size, 0, allowRepetition);

delete[] used;
delete[] perm;

int* nums = new int[size];
cout << "Enter the elements: ";
for (int i = 0; i < size; i++) {
    cin >> nums[i];
}

bool allowRepetition;
cout << "Allow repetition? (1 for yes, 0 for no): ";
cin >> allowRepetition;

permute(nums, size, allowRepetition);

delete[] nums;