Dynamic [i, n] range maximum query

bit.c

T range_max(const T *binary_indexed_tree, size_t size, size_t first)
{
	T value = T_MIN;
	for (; first < size; first |= first + 1)
		if (value < binary_indexed_tree[first])
			value = binary_indexed_tree[first];
	return value;
}

void increase(T *binary_indexed_tree, size_t pos, T value)
{
	for (; pos != (size_t) -1; pos = (pos & pos + 1) - 1)
		if (binary_indexed_tree[pos] < value)
			binary_indexed_tree[pos] = value;
}