a1/sum
1 #include<cstdio> 2 #include<iostream> 3 #include<algorithm> 4 #include<cstring> 5 #include<cmath> 6 #include<queue> 7 #include<map> 8 using namespace std; 9 #define MOD 1000000007 10 const int INF=0x3f3f3f3f; 11 const double eps=1e-5; 12 typedef long long ll; 13 #define cl(a) memset(a,0,sizeof(a)) 14 #define ts printf("***** "); 15 const int MAXN=1005; 16 int n,m,tt; 17 int a[MAXN]; 18 int main() 19 { 20 int i,j,k,ca=1; 21 #ifndef ONLINE_JUDGE 22 freopen("1.in","r",stdin); 23 #endif 24 scanf("%d",&tt); 25 while(tt--) 26 { 27 cin>>n; 28 int w,sum=0; 29 printf("Case %d: ",ca++); 30 for(i=0;i<n;i++) 31 { 32 int a; 33 scanf("%d",&a); 34 if(i==0) w=a; 35 sum+=a; 36 } 37 printf("%.6lf ",(double)w/sum); 38 } 39 }