<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.isRight = None
        self.isLeft = None


class Solution:

    def __init__(self):

        self.trie = TrieNode()


    def insert(self, binValStr):

        curr = self.trie

        for binDigit in binValStr:
            if binDigit == "1" and curr.isRight == None:
                curr.isRight = TrieNode()
                curr = curr.isRight
            elif binDigit == "1" and curr.isRight:
                curr = curr.isRight
            elif binDigit == "0" and curr.isLeft == None:
                curr.isLeft = TrieNode()
                curr = curr.isLeft
            elif binDigit == "0" and curr.isLeft:
                curr = curr.isLeft
  
            
    def getMaxXor(self, binValStr):

        maxXor = ''

        curr = self.trie

        for char in binValStr:

            if char == '1' and curr.isLeft:
                maxXor += '1'
                curr = curr.isLeft
            elif char == '0' and curr.isRight:
                maxXor += '1'
                curr = curr.isRight
            else:
                maxXor += '0'
                curr = curr.isLeft or curr.isRight

        return self.getDecimalNum(maxXor)



    def getDecimalNum(self, binStr):

        num = 0

        for i, binVal in enumerate(binStr[::-1]):

            if binVal == '1':
                num += 2**i

        return num



    def getBinarStr(self, num):

        binStr = ''

        while num:

            if num % 2 == 1:
                binStr = '1' + binStr
            else:
                binStr = '0' + binStr

            num = num//2

        padding = 31 - len(binStr)

        return '0'*padding + binStr


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

        for num in nums:

            binStr = self.getBinarStr(num)
            self.insert(binStr)

        maxXor = 0

        for num in nums:
            binStr = self.getBinarStr(num)

            maxXor = max(maxXor,self.getMaxXor(binStr))

        return maxXor


        
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