Delete the Middle Node of a Linked List

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode() : val(0), next(nullptr) {}
 *     ListNode(int x) : val(x), next(nullptr) {}
 *     ListNode(int x, ListNode *next) : val(x), next(next) {}
 * };
 */
class Solution {
public:
    ListNode* deleteMiddle(ListNode* head) {
        if(head->next==NULL)
        {
            return NULL;
        }
        ListNode* temp = head;
        int l=0;
        while(temp->next!=NULL)
        {
            l++;
            temp=temp->next;
        }
        // if(l%2==1)
        // {
        //    l=l/2;
        // }
        // else
        // {
        //     l=(l/2)+1;
        // }
        int i=0;
        ListNode* prev=NULL;
        ListNode* curr=head;
        while(i<((l+1)/2))
        {
            prev=curr;
             curr=curr->next;
            i++;
        }
        // ListNode* curr=prev->next;
        prev->next=curr->next;
        curr->next=NULL;
        delete(curr);
        return head;

    }
};