public static int MaxSubarrayXOR_b(int[] arr)
{
int result = 0;
if (arr != null && arr.Length > 0)
{
MaxSubarrayXORTrie root = new MaxSubarrayXORTrie();
Add(root, 0);
int pre_xor = 0;
for (int i = 0; i < arr.Length; i++)
{
// update current prefix xor and insert it into Trie
pre_xor = pre_xor ^ arr[i];
Add(root, pre_xor);
// Query for current prefix xor in Trie and update result if required
result = Math.Max(result, Search(root, pre_xor));
}
}
return(result);
}
private static void Add(MaxSubarrayXORTrie root, int pre_xor)
{
MaxSubarrayXORTrie temp = root;
for (int i = sizeof(Int32) - 1; i >= 0; i--)
{
int val = pre_xor & (1 << i);
if (temp.nodes[val] == null)
{
temp.nodes[val] = new MaxSubarrayXORTrie();
}
temp = temp.nodes[val];
}
}
private static int Search(MaxSubarrayXORTrie root, int pre_xor)
{
MaxSubarrayXORTrie temp = root;
for (int i = sizeof(Int32) - 1; i >= 0; i--)
{
// Find current bit in given prefix
int val = pre_xor & (1 << i);
// Traverse Trie, first look for a prefix that has opposite bit
if (temp.nodes[1 - val] != null)
{
temp = temp.nodes[1 - val];
}
else if (temp.nodes[val] != null)
{
// If there is no prefix with opposite bit, then look for same bit.
temp = temp.nodes[val];
}
}
return(pre_xor ^ (temp.value));
}
