<p>Given an integer array <code>nums</code>, return <em>the maximum result of </em><code>nums[i] XOR nums[j]</code>, where <code>0 &lt;= i &lt;= j &lt; n</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> nums = [3,10,5,25,2,8]
<strong>Output:</strong> 28
<strong>Explanation:</strong> The maximum result is 5 XOR 25 = 28.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> nums = [14,70,53,83,49,91,36,80,92,51,66,70]
<strong>Output:</strong> 127
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li>
	<li><code>0 &lt;= nums[i] &lt;= 2<sup>31</sup> - 1</code></li>
</ul>


class BinaryNode:

    def __init__(self):
        self._left = None
        self._right = None
        self._num = None

    def find_max(self, num: int, i: int) -> int:
        if i == -1:
            return self._num

        mask = 1 << i
        x = mask & num

        if self._right is None:
            return self._left.find_max(num, i - 1)
        elif self._left is None:
            return self._right.find_max(num, i - 1)
        elif x == 0:
            return self._right.find_max(num, i - 1)
        else:
            return self._left.find_max(num, i - 1)
    
    def add(self, num: int, i: int) -> None:
        if i == -1:
            self._num = num
            return
        mask = 1 << i
        x = num & mask
        if x == 0:
            if self._left is None:
                self._left = BinaryNode()
            self._left.add(num, i - 1)
        else:
            if self._right is None:
                self._right = BinaryNode()
            self._right.add(num, i - 1)
    

class Solution:
    def findMaximumXOR(self, nums: List[int]) -> int:

        def bit_length(num: int) -> int:
            i = 0
            while num > 0:
                i += 1
                num >>= 1
            return i
        
        l = max(bit_length(num) for num in nums)

        root = BinaryNode()
        for num in nums:
            root.add(num, l)

        max_xor = 0
        for num in nums:
            other = root.find_max(num, l)
            max_xor = max(max_xor, num ^ other)
        
        return max_xor
        
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