POJ 2976 Dropping tests [01分数规划]

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
using namespace std;
const int N=1005;
const double eps=1e-4;
inline int read(){
char c=getchar();int x=0,f=1;
while(c<'0'||c>'9'){if(c=='-')f=-1; c=getchar();}
while(c>='0'&&c<='9'){x=x*10+c-'0'; c=getchar();}
return x*f;
}
int n,k;
double a
,b
,c
;
bool check(double mid){
for(int i=1;i<=n;i++) c[i]=100*a[i]-mid*b[i];
sort(c+1,c+1+n);
double sum=0;
for(int i=1;i<=k;i++) sum+=c[n-i+1];
return sum>0;
}
void solve(){
double l=0.0,r=100.0;
while(r-l>eps){
double mid=(l+r)/2.0;
if(check(mid)) l=mid;
else r=mid;
}
printf("%.0f\n",l);
}
int main(){
freopen("in","r",stdin);
while(scanf("%d%d",&n,&k)!=EOF){
if(n==0&&k==0) break;
k=n-k;
for(int i=1;i<=n;i++) scanf("%lf",&a[i]);
for(int i=1;i<=n;i++) scanf("%lf",&b[i]);
solve();
}
}