<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 = [None, None]  # Use a list of fixed size 2 instead of a dictionary

class Trie:
    def __init__(self, nums):
        self.root = TrieNode()
        self.max_bits = max(num.bit_length() for num in nums)  # Find the maximum number of bits needed

    def insert(self, num):
        node = self.root
        for bit_p in range(self.max_bits - 1, -1, -1):  # Iterate from MSB to LSB
            bit = (num >> bit_p) & 1
            if not node.children[bit]:
                node.children[bit] = TrieNode()
            node = node.children[bit]

    def find_max_xor(self, num):
        node = self.root
        xor = 0
        for bit_p in range(self.max_bits - 1, -1, -1):  # Iterate from MSB to LSB
            bit = (num >> bit_p) & 1
            toggle_bit = 1 - bit
            if node.children[toggle_bit]:
                xor = (xor << 1) | 1
                node = node.children[toggle_bit]
            else:
                xor = xor << 1
                node = node.children[bit]
        return xor

    def get_max_xor(self, nums):
        result = 0
        for num in nums:
            self.insert(num)
            current_xor = self.find_max_xor(num)
            result = max(result, current_xor)
        return result

class Solution:
    def findMaximumXOR(self, nums: List[int]) -> int:
        trie = Trie(nums)
        return trie.get_max_xor(nums)
class TrieNode:
    def __init__(self):
        self.children = [None, None]  # Use a list of fixed size 2 instead of a dictionary

class Trie:
    def __init__(self, nums):
        self.root = TrieNode()
        self.max_bits = max(num.bit_length() for num in nums)  # Find the maximum number of bits needed

    def insert(self, num):
        node = self.root
        for bit_p in range(self.max_bits - 1, -1, -1):  # Iterate from MSB to LSB
            bit = (num >> bit_p) & 1
            if not node.children[bit]:
                node.children[bit] = TrieNode()
            node = node.children[bit]

    def find_max_xor(self, num):
        node = self.root
        xor = 0
        for bit_p in range(self.max_bits - 1, -1, -1):  # Iterate from MSB to LSB
            bit = (num >> bit_p) & 1
            toggle_bit = 1 - bit
            if node.children[toggle_bit]:
                xor = (xor << 1) | 1
                node = node.children[toggle_bit]
            else:
                xor = xor << 1
                node = node.children[bit]
        return xor

    def get_max_xor(self, nums):
        result = 0
        for num in nums:
            self.insert(num)
            current_xor = self.find_max_xor(num)
            result = max(result, current_xor)
        return result

class Solution:
    def findMaximumXOR(self, nums: List[int]) -> int:
        trie = Trie(nums)
        return trie.get_max_xor(nums)

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