hdu 4445 Crazy Tank(物理过程枚举)

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstdlib>
 4 #include<cstring>
 5 #include<string>
 6 #include<cmath>
 7 #include<map>
 8 #include<set>
 9 #include<vector>
10 #include<algorithm>
11 #include<stack>
12 #include<queue>
13 #include<cctype>
14 #include<sstream>
15 using namespace std;
16 #define pii pair<int,int>
17 #define LL long long int
18 const int eps=1e-8;
19 const int INF=1000000000;
20 const int maxn=100000+10;
21 const double pi=acos(-1);
22 const double ds=pi/1000;
23 const double g=9.8;
24 double l1,l2,r1,r2,h,v[210];
25 int ans,n;
26 int gao(double t)
27 {
28     int res=0;
29     for(int i=0;i<n;i++)
30     {
31         double vx=v[i]*cos(t);
32         double vy=v[i]*sin(t);
33         double vt=sqrt(2*g*h+vy*vy);
34         double t=(vt-vy)/g;
35         double d=vx*t;
36         if(d>=l2&&d<=r2) return 0;
37         else
38         {
39             if(d>=l1&&d<=r1)
40             {
41                 res++;
42             }
43         }
44     }
45     return res;
46 }
47 int main()
48 {
49     //freopen("in8.txt","r",stdin);
50     while(scanf("%d",&n)==1&&n)
51     {
52         scanf("%lf%lf%lf%lf%lf",&h,&l1,&r1,&l2,&r2);
53         for(int i=0;i<n;i++)
54         {
55             scanf("%lf",&v[i]);
56         }
57         ans=0;
58         for(double i=-(pi/2);i<=(pi/2);i+=ds)
59         {
60             ans=max(ans,gao(i));
61         }
62         printf("%d\n",ans);
63     }
64     return 0;
65 }