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NODE* middleNode(NODE* head) {
    NODE* slow = head;
    NODE* fast = head;
    while (fast->next != NULL && fast->next->next != NULL) {
        slow = slow->next;
        fast = fast->next->next;
    }
    return slow;
}

NODE* reverseList(NODE* head) {
    NODE* prev = NULL;
    NODE* curr = head;
    while (curr != NULL) {
        NODE* nextTemp = curr->next;
        curr->next = prev;
        prev = curr;
        curr = nextTemp;
    }
    return prev;
}

void mergeList(NODE* l1, NODE* l2) {
    NODE* l1_tmp;
    NODE* l2_tmp;
    while (l1 != NULL && l2 != NULL) {
        l1_tmp = l1->next;
        l2_tmp = l2...