void sort(int *data, int num)
{
    if (num == 2) {
        if (data[0] > data[1]) {
            int temp = data[0];
            data[0] = data[1];
            data[1] = temp;
        }
    }
    if (num > 2) {
        sort(data + 1, num - 1);
        sort(data, 2);
        sort(data + 1, num - 1);
    }
}