分析:想要完整覆盖,需要两个圆相交,得到有效的距离为下图中红线段,即:x=sqrt(r*r-1*1)
#include<iostream>
#include<cstdio>
#include<cstring>
#include <cmath>
#include <algorithm>
using namespace std;
const int NUM=605;
double a[NUM];
bool comp(double A,double B)
{
if(A>B) return 1;
else return 0;
}
int main()
{
int m,n,i,k;
double sum,ans;
cin>>m;
while(m--)
{
cin>>n;
for(i=0;i<n;i++)
cin>>a[i];
sort(a,a+n,comp);
sum=0;
for(i=0;i<n;i++)
{
//if(a[i]<1) continue;
ans=(double)2*sqrt(a[i]*a[i]-1);
sum+=ans;
if(sum>=20.0) break;
}
cout<<i+1<<endl;
}
return 0;
}