void Main()
{
    var a = new List<int> { 2, 4, 5, 7, 10 };
    var b = new List<int> { 13, 14, 15, 16, 17};
    Test(a, b);
    Console.WriteLine();

    a = new List<int> { 174, 521, 24, 224, 831, 179, 712, 97 };
    b = new List<int> { 281, 33, 122, 415, 611, 235, 737, 81 };
    Test(a, b);
}

void Test(List<int>a, List<int>b)
{
    XorSum(a, b).Dump();
    var max = FindMax(a, b);
    b.Dump();
    max.Dump();
}

int XorSum(List<int>a, List<int>b)
{
    return a.Zip(b).Select(t => t.First ^ t.Second).Sum();
}

int FindMax(List<int> a, List<int> b)
{
    while (FindIncreasingTranspose(a, b));
    return XorSum(a, b);
}

bool FindIncreasingTranspose(List<int> a, List<int> b)
{
    for (var i = 0; i < a.Count - 1; i++)
    {
        for (var j = i + 1; j < a.Count; j++)
        {
            if ((a[i] ^ b[j]) + (a[j] ^ b[i]) - (a[i] ^ b[i]) - (a[j] ^ b[j]) > 0)
            {
                (b[i], b[j]) = (b[j], b[i]);
                return true;
            }
        }
    }
    return false;
}