hdu5236 Article

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstdlib>
 4 #include<string>
 5 #include<cstring>
 6 #include<cmath>
 7 #define re(i,l,r) for(int i=(l);i<=(r);i++)
 8 #define rre(i,r,l) for(int i=(r);i>=(l);i--)
 9 using namespace std;
10 int n,x;
11 double p;
12 double dp[100010];
13 int main()
14 {
15     int t,tt;
16     scanf("%d",&t);tt=t;
17     while(t--)
18     {
19         scanf("%d%lf%d",&n,&p,&x);
20         re(i,1,n)dp[i]=(dp[i-1]+1)/(1-p);
21         double ans=dp[n]+x;
22         re(i,2,n)
23         {
24             int shu=n/i;
25             if(n%i)ans=min(ans,dp[shu+1]*(n%i)+dp[shu]*(i-n%i)+i*x);
26             else ans=min(ans,dp[shu]*i+i*x);
27         }
28         printf("Case #%d: %.6f\n",tt-t,ans);
29     }
30     return 0;
31 }