// write the values stored in ledStatus to the cube, ideally this method should
// be called atleast once every millisecond for multiplexing to give a smooth
// image and avoid flickering.
// displays 1 layer at a time at a high frequency to give a smooth image.
void CubeInterface::writeCube()
{
// 9th shift register controls cathodes
for(byte i = 0; i < 8; i++)
{
if(CATHODE_PINS[i] == currentLayer)
highBit();
else
lowBit();
} // for
// first 8 shift registers control anodes
for(byte i = 0; i < 64; i++)
if(ledStatus[ANODE_PINS[i][0]]
[ANODE_PINS[i][1]]
[currentLayer] == HIGH)
highBit();
else
lowBit();
if(currentLayer < 7)
currentLayer++;
else
currentLayer = 0;
latch();
} // writeCube
int sumRange(int i, int j)
{
if(i > j) return 0;
j++; //Note here!
int sum_i = 0, sum_j = 0;
for(int k = i; k > 0; k -= lowBit(k))
sum_i += bitree[k];
for(int k = j; k > 0; k -=lowBit(k))
sum_j += bitree[k];
return sum_j - sum_i;
}
int sum(int index) {
int sum = 0;
for (int i = index ; i > 0 ; i -= lowBit(i)) {
sum += C[i];
}
return sum;
}
int BIT_update(BIT_Handle handle, const unsigned int i, const int delta)
{
BIT_Array *pArray = (BIT_Array*)handle;
unsigned int j;
if (NULL == pArray)
{
ERROR("Invalid array handle %p.\n", handle);
return -1;
}
if (i >= pArray->length)
{
ERROR("Invalid index %u.\n", i);
return -1;
}
pArray->pSrc[i] += delta;
for (j = i; j <= pArray->length; j += lowBit(j))
{
pArray->pTree[j] += delta;
}
return 0;
}
int BIT_sum(BIT_Handle handle, const unsigned int n)
{
BIT_Array *pArray = (BIT_Array*)handle;
unsigned int i;
int sum = 0;
if (NULL == pArray)
{
ERROR("Invalid array handle %p.\n", handle);
return BIT_INVALID_SUM;
}
if (n > pArray->length)
{
ERROR("Invalid n %u, exceeds the array length %u.\n", n, pArray->length);
return BIT_INVALID_SUM;
}
/*
* 对于求数列的前n项和，只需找到n以前的所有最大子树，把其根节点的C加起来即可。
* 不难发现，这些子树的数目是n在二进制时1的个数，或者说是把n展开成2的幂方和时的项数.
* 1. 从下标为 n 的元素处开始往前计算.
* 2. i -= lowBit(i) 是因为 pTree[i] 包含了源数组中 lowBit(i) 个元素之和.
* 3. 下标从 1 开始，故结束条件是下标达到 0.
*/
for (i = n; i > 0; i -= lowBit(i))
{
sum += pArray->pTree[i];
}
return sum;
}
void update(int i, int val) {
int inc = val - input[i];
for (int k = i + 1; k <= len; k += lowBit(k)) {
sum[k] += inc;
}
input[i] = val;
}
int getSum(int i) {
int ans = 0;
for (int k = i + 1; k > 0; k -= lowBit(k)) {
ans += sum[k];
}
return ans;
}
void add(int index, int delta = 1) {
while(index <= len) {
array[index] += delta;
index += lowBit(index);
}
}
int sum(int index) {
int res = 0;
while(index > 0) {
res+=array[index];
index -= lowBit(index);
}
return res;
}
BIT_Handle BIT_create(const unsigned int length)
{
BIT_Array *pArray = NULL;
size_t memorySize;
unsigned int i, j;
if (0 == length)
{
ERROR("length %u should be >= 1.\n", length);
return NULL;
}
pArray = calloc(1, sizeof(*pArray));
if (NULL == pArray)
{
ERROR("Failed to allocate memory.\n");
return NULL;
}
/* subscript starts from 1, so the element at [0] is not used */
pArray->length = length;
memorySize = (pArray->length + 1) * sizeof(pArray->pSrc[0]);
pArray->pSrc = calloc(1, memorySize);
pArray->pTree = calloc(1, memorySize);
if (NULL == pArray->pSrc || NULL == pArray->pTree)
{
ERROR("Failed to allocate memory for array elements.\n");
BIT_destroy(pArray);
}
for (i = 1; i <= pArray->length; ++i)
{
pArray->pSrc[i] = i;
}
for (i = 1; i <= pArray->length; ++i)
{
pArray->pTree[i] = pArray->pSrc[i];
/* tree[i] 对 src[i] 之前的 lowBit(i) 个元素负责 */
for (j = i - 1; j > i - lowBit(i); --j)
{
pArray->pTree[i] += pArray->pSrc[j];
}
}
return (BIT_Handle)pArray;
}
void add(int index, int value) {
for (int i = index ; i <= size ; i += lowBit(i)) {
C[i] += value;
}
}
void add(int beg, int end, int val)
{
for(int i = beg; i < end; i += lowBit(i))
bitree[i] += val;
}
NumArray(vector<int> &nums): len(nums.size()), sum(len + 1, 0), input(nums) {
for (int i = 0; i < len; ++i) {
for (int j = i + 1; j > 0; j -= lowBit(j))
sum[i+1] += nums[j-1];
}
}
