Convert Sorted List to Binary Search Tree LeetCode solution in C++

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class Solution {
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 public:
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  typedef vector<int>::iterator vecIt;
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  TreeNode *buildTree(vector<int> &listToVec, vecIt start, vecIt end) {
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    if (start >= end) return NULL;
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    vecIt midIt = start + (end - start) / 2;
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    TreeNode *newNode = new TreeNode(*midIt);
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    newNode->left = buildTree(listToVec, start, midIt);
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    newNode->right = buildTree(listToVec, midIt + 1, end);
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    return (newNode);
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  }
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  TreeNode *sortedListToBST(ListNode *head) {
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    vector<int> listToVec;
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    while (head) {
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      listToVec.push_back(head->val);
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      head = head->next;
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    }
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    return (buildTree(listToVec, listToVec.begin(), listToVec.end()));
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  }
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};