<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 TrieNode:
    def __init__(self):
        self.children = {}

class Trie:
    def __init__(self):
        self.root = TrieNode()
    def insert(self, binary):
        cur = self.root
        for bit in binary:
            if bit not in cur.children: cur.children[bit] = TrieNode()
            cur = cur.children[bit]
    def find(self, binary):
        num = []
        cur = self.root
        for bit in binary:
            if bit == '1':
                if '0' in cur.children:
                    num.append('0')
                    cur = cur.children['0']
                else:
                    num.append('1')
                    cur = cur.children['1']
            else:
                if '1' in cur.children:
                    num.append('1')
                    cur = cur.children['1']
                else:
                    num.append('0')
                    cur = cur.children['0']
        return int(''.join(num), 2) ^ int(binary, 2)

class Solution:
    def findMaximumXOR(self, nums: List[int]) -> int:
        trie = Trie()
        res = 0
        for num in nums:
            binary =  bin(num).replace("0b", "").zfill(32)
            trie.insert(binary)
        for num in nums:
            binary =  bin(num).replace("0b", "").zfill(32)
            res = max(res, trie.find(binary))
        return res
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