給定整數m以及n各數字A1,A2,..An，將數列A中所有元素兩兩異或，共能得到n(n-1)/2個結果，請求出這些結果中大於m的有多少個

public class Main 
{
    private static class TrieTree 
    {
        TrieTree[] next = new TrieTree[2];
        int count = 1;
    }
    private static long solve(int[] a, int m) 
    {
        TrieTree trieTree = buildTrieTree(a);
        long result = 0;
        for (int i = 0; i < a.length; i++) 
        {
            result += queryTrieTree(trieTree, a[i], m, 31);
        }
        return result / 2;
    }
    private static long queryTrieTree(TrieTree trieTree, int a, int m, int index) 
    {
        if(trieTree == null)
            return 0;
        TrieTree current = trieTree;
        for (int i = index; i >= 0; i--) 
        {
            int aDigit = (a >> i) & 1;
            int mDigit = (m >> i) & 1;
            if(aDigit == 1 && mDigit == 1) 
            {
                if(current.next[0] == null)
                    return 0;
                current = current.next[0];
            } 
            else if (aDigit == 0 && mDigit == 1) 
            {
                if(current.next[1] == null)
                    return 0;
                current = current.next[1];
            } 
            else if (aDigit == 1 && mDigit == 0) 
            {
                long p = queryTrieTree(current.next[1], a, m, i - 1);
                long q = current.next[0] == null ? 0 : current.next[0].count;
                return p + q;
            } 
            else if (aDigit == 0 && mDigit == 0) 
            {
                long p = queryTrieTree(current.next[0], a, m, i - 1);
                long q = current.next[1] == null ? 0 : current.next[1].count;
                return p + q;
            }
        }
        return 0;
    }
    private static TrieTree buildTrieTree(int[] a) 
    {
        TrieTree trieTree = new TrieTree();
        for (int i = 0; i < a.length; i++) 
        {
            TrieTree current = trieTree;
            for (int j = 31; j >= 0; j--) 
            {
                int digit = (a[i] >> j) & 1;
                if(current.next[digit] == null) 
                {
                    current.next[digit] = new TrieTree();
                } 
                else 
                {
                    current.next[digit].count ++;
                }
                current = current.next[digit];
            }
        }
        return trieTree;
    }
}