<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 Solution:
    def __init__(self):
        self.trie = {}

    def findMaximumXOR(self, nums: List[int]) -> int:
        # Build the Trie
        root = self.trie
        L = len(bin(max(nums)))-2
        for num in nums:
            node = root
            for i in range(L, -1, -1):
                bit = (num >> i) & 1
                if bit not in node:
                    node[bit] = {}
                node = node[bit]
        
        max_xor = 0
        for num in nums:
            node = root
            cur_xor = 0
            for i in range(L, -1, -1):
                bit = (num >> i) & 1
                rev_bit = 1-bit
                if rev_bit in node:
                    cur_xor = (cur_xor << 1) | 1
                    node = node[rev_bit]
                else:
                    cur_xor = (cur_xor << 1) | 0
                    node = node[bit]
            max_xor = max(max_xor, cur_xor)
        return max_xor
                
                

        '''
        def decimal_to_binary_list(decimal_list):
            max_length = len(bin(max(decimal_list))) - 2
            binary_list = [format(num, f'0{max_lenght}b') for num in decimal_list]
		return binary_list

        binary_list = decimal_to_binary_list(decimal_list)
	
	    max_length = len(binary_list[0])

	    max_xor = 0

        n = len(binary_list)
        # find pivot number
        pivot_number = []
        for binary in binary_list:
            if binary[0] == "1":
        '''
        
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