108_c

        int size = nums.size();
        if(size < 1)
            return NULL;
        int mid = size / 2;
        int i = 0;
        TreeNode* tree = new TreeNode(nums[mid]);
        TreeNode* out = tree;
        for(i = mid-1;i >= 0;i--){
            TreeNode* le = new TreeNode(nums[i]);
            tree->left = le;
            tree = le;
        }
        tree = out;
        for(i = mid+1; i < size; i ++){
            TreeNode* le = new TreeNode(nums[i]);
            tree->right = le;
            tree = le;
        }
        return out;
        
    int size = nums.size();
    if (size==0) return NULL;
    int mid = size/2;
    vector<int> left,right;
    for(int i=0;i<mid;i++) left.push_back(nums[i]);
    for(int i= mid+1;i<size;i++) right.push_back(nums[i]);
    TreeNode *root = new TreeNode(nums[mid]);
    root->left = sortedArrayToBST(left);
    root->right = sortedArrayToBST(right);
    return root;