#include <bits/stdc++.h> using namespace std; double f(int n,int x) { if(n==0) return 1; else if(n==1) return x; else return ((2*n-1)*x*f(n-1,x)-(n-1)*f(n-2,x))*1.0/n; } int main() { int n,x; cin>>n>>x; cout<<f(n,x)<<endl; return 0; }
标签:std,return,int,else,打卡,5.18 From: https://www.cnblogs.com/Sunyiran/p/17412494.html