<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 Node
{
    public:
    Node * links[2]={nullptr, nullptr};

    bool contain(int bit)
    {
        return (links[bit]!=NULL);

    }
    Node * get(int bit)
    {
        return links[bit];
    }
    void put(Node * node,int bit)
    {
        links[bit]=node;
    }
};

class Solution {
public:
    Node * root=new Node();
    int findMaximumXOR(vector<int>& nums) {
        for(int i=0;i<nums.size();i++)
        {
          bitset<32> b(nums[i]); 
        string n = b.to_string(); 
            Node * node=root;
            for(int j=0;j<32;j++)
            {
                if(!node->contain(n[j]-'0'))
                {
                    node->put(new Node(),n[j]-'0');
                }
                node=node->get(n[j]-'0');
            }
            


        }
        long long int ans=0;
        for(int i=0;i<nums.size();i++)
        {
           long long int m=0;
            bitset<32> b(nums[i]); 
        string n = b.to_string(); 
            Node * node=root;
            for(int j=0;j<32;j++)
            {
                int bit=n[j]-'0';
                if(node->contain(!bit))
                {
                    m =m+pow(2,31-j);
                    node=node->get(!bit);
                }
                else
                {
                     node=node->get(bit);
                }
                
            }
            ans=max(ans,m);
            


        }
        return ans;

    }
};
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