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Intuition\nThe problem involves merging nodes between zeros in a linked list. The key idea is to traverse the list, accumulate the sum of values between two zer
# Intuition\nThe problem involves merging nodes between zeros in a linked list. The key idea is to traverse the list, accumulate the sum of values between two zeros, and then create a new node with this sum. This process is repeated for each segment of the list separated by zeros.\n\n# Approach\n1. Initialize a new dummy head node to help construct the resulting linked list.\n2. Traverse the input list, skipping the initial zero node.\n3. Use a variable to accumulate the sum of node values until the next zero node is encountered.\n4. When a zero node is found, create a new node with the accumulated sum and append it to the resulting list.\n5. Reset the sum and continue until the end of the list is reached.\n6. Return the next node of the dummy head as the result.\n\n# Complexity\n- Time complexity:\nO(n) where n is the number of nodes in the linked list. We traverse each node exactly once.\n\n- Space complexity:\nO(1) for the additional pointers and variables used.\n\n# Code\n```\nclass Solution {\npublic:\n    ListNode* mergeNodes(ListNode* head) {\n        // Create a new dummy head for the result list\n        ListNode* resultHead = new ListNode(0);\n        ListNode* temp = resultHead;\n\n        // Skip the initial zero node\n        head = head->next;\n\n        // Initialize sum to accumulate values\n        long long sum = 0;\n\n        // Traverse the list\n        while (head != nullptr) {\n            // Add the current node\'s value to sum\n            sum += head->val;\n\n            // If a zero node is encountered\n            if (head->val == 0) {\n                // Create a new node with the sum and append it to the result list\n                ListNode* newNode = new ListNode(sum);\n                temp->next = newNode;\n                temp = newNode;\n                \n                // Reset sum for the next segment\n                sum = 0;\n            }\n\n            // Move to the next node\n            head = head->next;\n        }\n\n        // Return the next node of dummy head as the result list head\n        return resultHead->next;\n    }\n};\n```\n# Explanation\n1. **Definition of ListNode:** A basic structure to represent a node in the linked list.\n2. **Result List Initialization:** A dummy node resultHead is used to simplify list construction.\n3. **Traversal and Summation:** We traverse the list, skipping the initial zero, and accumulate values in sum.\n4. **Zero Node Handling:** When a zero is encountered, a new node with the accumulated sum is created and appended to the result list. The sum is then reset for the next segment.\n5. **Final List:** The dummy node\'s next pointer points to the head of the resulting list, which is returned.
['C++']