### LeetCode Challenge #2181. Merge Nodes in Between Zeros

You are given the `head` of a linked list, which contains a series of integers separated by `0`‘s. The beginning and end of the linked list will have `Node.val == 0`.

For every two consecutive `0`‘s, merge all the nodes lying in between them into a single node whose value is the sum of all the merged nodes. The modified list should not contain any `0`‘s.

Return the `head` of the modified linked list.

Example 1:

```Input: head = [0,3,1,0,4,5,2,0]
Output: [4,11]
Explanation:
The above figure represents the given linked list. The modified list contains
- The sum of the nodes marked in green: 3 + 1 = 4.
- The sum of the nodes marked in red: 4 + 5 + 2 = 11.
```

Example 2:

```Input: head = [0,1,0,3,0,2,2,0]
Output: [1,3,4]
Explanation:
The above figure represents the given linked list. The modified list contains
- The sum of the nodes marked in green: 1 = 1.
- The sum of the nodes marked in red: 3 = 3.
- The sum of the nodes marked in yellow: 2 + 2 = 4.
```

Constraints:

• The number of nodes in the list is in the range `[3, 2 * 105]`.
• `0 <= Node.val <= 1000`
• There are no two consecutive nodes with `Node.val == 0`.
• The beginning and end of the linked list have `Node.val == 0`.
##### Video Solution
###### Java Solution
```				```
class Solution {
ListNode dummy = new ListNode(-1);
ListNode ans = dummy ;
int sum = 0 ;
while(curr!=null){

if(curr.val !=0){
sum += curr.val;
}else{
ListNode temp = new ListNode(sum);
dummy.next = temp ;
dummy = dummy.next;
sum = 0 ;
}
curr = curr.next;
}
return ans.next;
}
}
```
```