<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 Node:
#     __init__()
#         self.zero = None
#         self.one = None
#         self.last = False


class Solution:
    def findMaximumXOR(self, nums: List[int]) -> int:
        trie = [None, None]
        max_xor = 0
        L = len(bin(max(nums))) - 2
        nums = [[(x >> i) & 1 for i in range(L)][::-1] for x in nums]
        n = trie
        for bit in nums[0]:
            n[bit] = [None, None]
            n = n[bit]
        for num in nums[1:]:
            node = trie
            xor_node = trie
            cur_xor = 0
            for bit in num:
                cur_xor <<= 1
                if node[bit] == None:
                    node[bit] = [None, None]
                node = node[bit]
                if xor_node[1 - bit] != None:
                    cur_xor |= 1
                    xor_node = xor_node[1 - bit]
                else:
                    xor_node = xor_node[bit]
            max_xor = max(max_xor, cur_xor)
        return max_xor
            
        

        
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