<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 Solution {
public:
    int findMaximumXOR(std::vector<int>& nums) {
        int maxNum = *std::max_element(nums.begin(), nums.end());
        int msbPosition = findMostSignificantBitPosition(maxNum);
        
        return buildMaximumXOR(nums, msbPosition);
    }
    
private:
    int findMostSignificantBitPosition(int num) {
        for (int i = 31; i >= 0; --i) {
            if ((num & (1 << i)) != 0) {
                return i;
            }
        }
        return 0;
    }
    
    int buildMaximumXOR(const std::vector<int>& nums, int msbPosition) {
        int result = 0;
        int prefixMask = 0;
        std::unordered_set<int> prefixes;
        
        for (int i = msbPosition; i >= 0; --i) {
            prefixMask |= (1 << i);
            
            int candidateResult = result | (1 << i);
            prefixes.clear();
            
            for (int num : nums) {
                int prefix = num & prefixMask;
                if (prefixes.count(candidateResult ^ prefix)) {
                    result = candidateResult;
                    break;
                }
                prefixes.insert(prefix);
            }
        }
        
        return result;
    }
};
//Stolen From Kartikdevsharmaa
76551