概率与期望
#include<iostream>
#include<cstring>
#include<cstdio>
#include<cmath>
using namespace std;
inline int read(){
int x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
return x*f;
}
int N,n,k,m;
double p[1001],ans[1001];
int main(){
freopen("tribbles.in","r",stdin);
freopen("tribbles.out","w",stdout);
N=read();
for(int t=1;t<=N;t++){
n=read();k=read();m=read();
for(int i=0;i<n;i++)
scanf("%lf",&p[i]);
memset(ans,0,sizeof(ans));
ans[m]=p[0];
for(int i=m-1;i>=1;i--){
ans[i]=p[0];
for(int j=1;j<n;j++)
ans[i]+=p[j]*pow(ans[i+1],j);
}
double P=1;
for(int i=1;i<=k;i++)
P*=ans[1];
printf("Case #%d: %.7lf\n",t,P);
}
return 0;
}