<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 {
    
    public:
    TrieNode**children;

    TrieNode(){
        children = new TrieNode*[2];
        children[0] = NULL;
        children[1] = NULL;
    }
};
class Trie{

    public:
    TrieNode *root;

    Trie() {
        root = new TrieNode();
    }

    void insert(int x){
        TrieNode *temp = root;
        for(int i=31;i>=0;i--){
            // int x=(num>>i)&1;
            if(temp->children[((x>>i)&1)]==NULL) {
                temp->children[((x>>i)&1)] = new TrieNode();
            }
            temp = temp->children[((x>>i)&1)];
        }
    }

    int find(int x){
        int ans = 0;
        TrieNode *temp = root;
        for(int i=31;i>=0;i--){
            int value = (x>>i)&1;
            
            if(temp->children[value^1]) {
                ans = ans^(1<<i);
                temp = temp->children[value^1];
            }else{
                temp = temp->children[value];
            }  
        }
        return ans;
    }

};
class Solution {
public:
    int findMaximumXOR(vector<int>& nums) {
       
        Trie t;
        for(int i=0;i<nums.size();i++){
            t.insert(nums[i]);
        }
        int ans = 0;
        for(int i=0;i<nums.size();i++){
            ans = max(ans,t.find(nums[i]));
        }
        return ans;
    }
};
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