poj2976 Dropping tests (01分数规划)

裸题。

 1 #include<cstdio>
 2 #include<cstring>
 3 #include<algorithm>
 4 #include<vector>
 5 #include<queue>
 6 #include<cmath>
 7 #include<ctime>
 8 #define LL long long int
 9 #define inf 0x3f3f3f3f
10 using namespace std;
11 const int maxn=1010;
12 
13 LL rd(){
14    LL x=0;char c=getchar();int neg=1;
15    while(c<'0'||c>'9'){if(c=='-') neg=-1;c=getchar();}
16    while(c>='0'&&c<='9') x=x*10+c-'0',c=getchar();
17    return x*neg;
18 }
19 
20 int N,K,A[maxn],B[maxn];double x[maxn]; 
21 
22 bool judge(double r){
23     for(int i=1;i<=N;i++) x[i]=A[i]-B[i]*r;
24     sort(x+1,x+1+N);double re=0;
25     for(int i=N;i>K;i--){
26         re+=x[i];
27     }return re>=0;
28 }
29 
30 int main(){
31     int i,j,k;
32     while(1){
33         N=rd(),K=rd();if(!N) break;
34         for(i=1;i<=N;i++) A[i]=rd();
35         for(i=1;i<=N;i++) B[i]=rd();
36         double l=0,r=1;
37         while(fabs(l-r)>1e-6){
38             double m=(l+r)/2;
39             if(judge(m)) l=m+1e-6;
40             else r=m-1e-6;
41         }printf("%d\n",(int)(l*100+0.5));
42     }
43     return 0;
44 }

 

posted @ 2018-09-03 22:55  Ressed  阅读(182)  评论(0)  编辑  收藏  举报