private static LeetCode108TreeNode BuildBSTInPreOrderLeftMiddle(int left, int right)
{
if (left > right)
{
return(null);
}
// find the middle point
var middleIndex = (right - left) / 2 + left;
// construct the node
var root = new LeetCode108TreeNode(inputNums[middleIndex]);
// build the left tree
root.left = BuildBSTInPreOrderLeftMiddle(left, middleIndex - 1);
// build the right tree
root.right = BuildBSTInPreOrderLeftMiddle(middleIndex + 1, right);
return(root);
}
public LeetCode108TreeNode(int val = 0, LeetCode108TreeNode left = null, LeetCode108TreeNode right = null)
{
this.val = val;
this.left = left;
this.right = right;
}
