int *grayCode(int n, int *returnSize) {
if (n < 0) {
*returnSize = 0;
return NULL;
}
if (n == 0) {
*returnSize = 1;
int *r = malloc(sizeof(int) * (*returnSize));
r[0] = 0;
return r;
}
int sz1;
int *r1 = grayCode(n - 1, &sz1);
*returnSize = 2 * sz1;
int *r = malloc(sizeof(int) * (*returnSize));
memcpy(r, r1, sizeof(int) * sz1);
int i, bias = 1 << (n - 1);
for (i = sz1; i != *returnSize; i++) {
// reflect and add bias, That's why Gray code also named
// Reflected-Binary-Code
r[i] = r[*returnSize - 1 - i] + bias;
}
free(r1);
return r;
}
void SubSetTest::testGrayCode( void )
{
vector<string> res = grayCode(3);
for (int i = 0; i < res.size(); ++i)
{
cout<<res[i]<<" ";
}
cout<<endl;
}
int main() {
int rank = 5;
int sz;
int *r = grayCode(rank, &sz);
int i, j;
for (i = 0; i != sz; i++) {
// show binary code
for (j = rank - 1; j >= 0; j--) {
printf("%d", r[i] & (1 << j) ? 1 : 0);
}
printf("\n");
}
return 0;
}
vector<int> grayCode(int n) {
vector<int> v ;
if(n == 0 ){
v.push_back(0);
}else if(n == 1) {
v.push_back(0); v.push_back(1);
}else{
vector<int> w = grayCode(n-1);
for(int i =0 ; i< w.size(); ++ i)
v.push_back(w[i]) ;
for(int i = w.size()-1; i>=0 ; --i)
v.push_back( (1<<(n-1)) | w[i]);
}
return v;
}
std::vector<int> grayCode(int n) {
std::vector<int> gray_vec;
if (n == 0) return std::vector<int>{0};
if (n == 1) {
gray_vec.push_back(0);
gray_vec.push_back(1);
return gray_vec;
}
auto sub_vec = grayCode(n - 1);
gray_vec.insert(gray_vec.begin(), sub_vec.begin(), sub_vec.end());
for (int i = sub_vec.size() - 1; i >= 0; i--){
int shift_num = 1 << (n - 1);
gray_vec.push_back(sub_vec[i] + shift_num);
}
return gray_vec;
}
vector<int> grayCode(int n) {
// Start typing your C/C++ solution below
// DO NOT write int main() function
vector<int> ret;
if (n == 0) {
ret.push_back(0);
} else {
ret = grayCode(n - 1);
vector<int> nxt = ret;
reverse(nxt.begin(), nxt.end());
for (int i = 0; i < nxt.size(); ++i) {
nxt[i] |= (1 << (n - 1));
}
ret.insert(ret.end(), nxt.begin(), nxt.end());
}
return ret;
}
vector<string> SubSetTest::grayCode( int n )
{
vector<string> code;
code.resize(pow(2, n));
if(n == 1){
code[0] = "0";
code[1] = "1";
return code;
}
vector<string> last = grayCode(n - 1);
for(int i = 0; i < last.size(); ++i){
code[i] = "0" + last[i];
code[code.size() - 1 - i] = last[i] + "1";
}
return code;
}
vector<int> grayCode(int n)
{
vector<int> tmp;
if(n == 1)
{
tmp.push_back(0), tmp.push_back(1);
return tmp;
}
else if(n == 0)
{
tmp.push_back(0);
return tmp;
}
tmp = grayCode(n-1);
vector<int> ans = tmp;
for(int i = tmp.size()-1; i >= 0; i--)
ans.push_back(tmp[i] + (1 << (n-1)));
return ans;
}
vector<int> grayCode(int n) {
vector<int> res;
if (n == 0) {
res.push_back(0);
} else if (n == 1) {
res.push_back(0);
res.push_back(1);
} else if (n > 1) {
vector<int> tmp = grayCode(n - 1);
for (int i : tmp) {
res.push_back(i);
}
tmp = reverseList(tmp);
for (int i : tmp) {
res.push_back(i | (1 << (n - 1)));
}
}
return res;
}
vector<int> grayCode(int n) {
if (n == 0) {
vector<int> result;
result.push_back(0);
return result;
}
if (n == 1) {
vector<int> result;
result.push_back(0);
result.push_back(1);
return result;
}
vector<int> ret = grayCode(n - 1), result(ret.size() * 2, 0);
for (int i = 0; i < (int) ret.size(); i += 2) {
result[2 * i] = ret[i] << 1;
result[2 * i + 1] = (ret[i] << 1) + 1;
result[2 * i + 2] = (ret[i + 1] << 1) + 1;
result[2 * i + 3] = ret[i + 1] << 1;
}
return result;
}
std::vector<int> grayCode(int n)
{
std::vector<int> graySeq;
if(n == 0)
{
graySeq.push_back(0);
return graySeq;
}
if(n == 1)
{
graySeq.push_back(0);
graySeq.push_back(1);
return graySeq;
}
graySeq = grayCode(n-1);
int count = graySeq.size();
int movedBit = n-1;
for(int i=count-1; i>=0; i--)
{
graySeq.push_back(graySeq[i]+(1<<movedBit));
}
return graySeq;
}
int main(void)
{
int *res, n;
res = grayCode(1, &n);
return(0);
}
int main(){
grayCode(3);
return 0;
}
