<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* links[2];
    bool containsKey(int bit){
        return (links[bit]!=NULL);
    }
    Node* get(int bit){
        return links[bit];
    }
    void put(int bit,Node* node){
        links[bit]=node;
    }
};

class Trie{
    private:
        Node* root;
    public:
        Trie(){
            root=new Node();
        }
        void insert(int num){
            Node* node=root;
            for(int i=31;i>=0;i--){
                int bit=(num>>i)&1;
                if(!node->containsKey(bit)){
                    node->put(bit,new Node());
                }
                node=node->get(bit);
            }
        }
        int getMax(int num){
            int maxSum=0;
            Node* node=root;
            for(int i=31;i>=0;i--){
                int bit=(num>>i)&1;
                if(node->containsKey(1-bit)){
                    maxSum|=(1<<i);
                    node=node->get(1-bit);
                }
                else node=node->get(bit);
            }
            return maxSum;
        }
};
class Solution {
public:
    int findMaximumXOR(vector<int>& nums) {
        Trie trie;
        for(auto &it:nums) trie.insert(it);
        int maxi=0;
        for(auto &it:nums) maxi=max(maxi,trie.getMax(it));
        return maxi;
    }
};
auto init=[](){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    return 'c';
}();
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