剑指offer——面试题15.1：判断一个数是否为2的整数次方

 1 #include"iostream"
 2 using namespace std;
 3 
 4 bool IsTwoPower(int n)
 5 {
 6     return !((n-1)&n);
 7 }
 8 
 9 int main()
10 {
11     int n;
12     while(cin>>n)
13     {
14         if(n==0)
15         {
16             cout<<"no"<<endl;
17             continue;
18         }
19         if(IsTwoPower(n))
20             cout<<"yes"<<endl;
21         else
22             cout<<"no"<<endl;
23     }
24     return 0;
25 }