<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>

#pragma GCC optimize("Ofast")
#pragma GCC taget("avx,avx2,fma")
static const int _ = [] { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); std::cout.tie(nullptr); return 0; }();

class TrieNode{
    public:
        TrieNode* arr[2];
        TrieNode(){
            for(int i=0;i<2;i++){
                arr[i]=nullptr;
            }
        }
        bool isContains(int n){
            return arr[n]!=nullptr;
        }
};
class Trie{
    public:
        TrieNode* root;
        Trie(){
            root=new TrieNode();
        }
        void insert(int n){
            TrieNode* temp=root;
            for(int i=31;i>=0;i--){
                int bit=(n>>i) & 1;
                if(temp->isContains(bit)){
                    temp=temp->arr[bit];
                }
                else{
                    temp->arr[bit]=new TrieNode();
                    temp=temp->arr[bit];
                }
            }
        }
        int findTarget(int n){
            TrieNode* temp=root;
            int xorVal=0;
            for(int i=31;i>=0;i--){
                int bit=(n>>i) & 1;
                if(temp->isContains(1-bit)){
                    xorVal=xorVal | 1<<i;
                    temp=temp->arr[1-bit];
                }
                else{
                    temp=temp->arr[bit];
                }
            }
            return xorVal;
        }
};


class Solution {
public:
    int findMaximumXOR(vector<int>& nums) {
        Trie* trie=new Trie();
        for(int num:nums){
            trie->insert(num);
        }
        int ans=0;
        for(int it:nums){
            ans=max(ans,trie->findTarget(it));
        }
        return ans;
    }
};
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