<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>

struct Node{
    Node *link[2];
};

class Solution {
public:
    

    Node* root;
    void insert(vector<int>& num){
        Node *node = root;
        for(int i=0;i<32;i++){
            if(node->link[num[i]]==NULL){
                node->link[num[i]]=new Node();
            }
            node=node->link[num[i]];
        }
    }
    vector<vector<int>> bitsarray;
    void bits(int num){
        vector<int> bit(32.0);
        int j=31;
        while(num!=0){
            bit[j--]=num%2;
            num/=2;
        }
        bitsarray.push_back(bit);
    }

    int maxXor(vector<int>& num){
        Node* node=root;
        int ans=0;
        for(int i=0;i<32;i++){
            if((node->link[1-num[i]])!=NULL){
                ans|=(1<<(31-i));
                node=node->link[1-num[i]];
            }
            else{
                node=node->link[num[i]];
            }
        }

        return ans;
    }
    int findMaximumXOR(vector<int>& nums) {
        root = new Node();

        for(int i=0;i<nums.size();i++){
            bits(nums[i]);
        }

        for(int i=0;i<nums.size();i++){
            insert(bitsarray[i]);
        }

        int ans=0;
        for(int i=0;i<nums.size();i++){
            ans=max(ans,maxXor(bitsarray[i]));
        }

        return ans;

    }
};
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