题目：https://www.nowcoder.com/questionTerminal/0984adf1f55a4ba18dade28f1ab15003

1 #include 
     
       2 #include 
      
        3 using namespace std; 4  5 const int maxn = 1000000 + 5; 6 int f[maxn]; 7  8 void db(){ 9     f[0] = 7 % 3;10     f[1] = 11 % 3;11     for (int i = 2; i < maxn; i++){12         f[i] = (f[i - 1] + f[i - 2]) % 3;13     }14 }15 16 int main(){17     db();18     int n;19     while (cin >> n){20         if (f[n] == 0){21             cout << "Yes" << endl;22         }23         else{24             cout << "No" << endl;25         }26     }27 //    system("pause");28     return 0;29 }