腾讯笔试:>格雷码

/*    腾讯笔试:>格雷码*/vector<int> Gray_Create(int n){    vector<int> res;    for (int i = 0; i < (1 << n); ++i)    {        res.push_back(i ^ (i >> 1));    }    return res;}//void test()//{//  vector<int>res = Gray_Create(3);//  for (int i = 0; i < res.size(); ++i)//      cout << res[i];//}vector<string> getGray(int n) {    // write code here    vector<string> res;    if (n == 1) {        res.push_back("0");        res.push_back("1");        return res;    }    vector<string> v = getGray(n - 1);    int len = pow(2, n - 1);    for (int i = 0; i < len; i++) {        res.push_back("0" + v[i]);    }    for (int i = len - 1; i >= 0; i--) {        res.push_back("1" + v[i]);    }    return res;}//void test()//{//  vector<string>res=getGray(3);//  for (int i = 0; i < res.size(); ++i)//              cout << res[i]<<endl;//}