- #include <iostream>
- using namespace std;
- double f(int,int);
- int main()
- {
- int n,x;
- cout<<"please enter n,x";
- cin>>n>>x;
- cout<<f(n,x)<<endl;
- system("pause");
- return 0;
- }
- double f(int n,int x)
- {
- double s=0;
- if(n==0) s=1;
- else if(n==1) s=x;
- else s=((2*n-1)*x-f(n-1,x)-(n-1)*f(n-2,x))/2;
- return s;
- }
来源: http://www.bubuko.com/infodetail-2489528.html