// return [lo .. hi] tree
private static LeetCode654TreeNode Build(int[] nums, int lo, int hi)
{
if (lo > hi)
{
return(null);
}
var index = 0;
var max = int.MinValue;
for (int i = lo; i <= hi; i++)
{
if (max < nums[i])
{
max = nums[i];
index = i;
}
}
var root = new LeetCode654TreeNode(max);
root.left = Build(nums, lo, index - 1);
root.right = Build(nums, index + 1, hi);
return(root);
}
public LeetCode654TreeNode(int val = 0, LeetCode654TreeNode left = null, LeetCode654TreeNode right = null)
{
this.val = val;
this.left = left;
this.right = right;
}
