struct ListNode* removeZeroSumSublists(struct ListNode* head){
    struct ListNode* dum = (struct ListNode*)malloc(sizeof(struct ListNode));
    dum->next = head;
    struct ListNode* cur = dum;
    int sum = 0;
    while (cur != NULL)
    {
        struct ListNode* search = cur->next;
        sum = 0;
        while (search != NULL)
        {
            sum += search->val;
             if (sum == 0)
            {
                cur->next = search->next;
            }
            search = search->next;
        }
        cur = cur->next;
    }
    return dum->next;
}